As is the case with most everything else in Bill Belichick's empire, the Patriots will survive the loss of personnel head Scott Pioli, who is off to run the Kansas City Chiefs. There may be some bumps in the transition, but the Pats will figure it out eventually as they always do. They will continue to acquire good players.

And that's because Belichick remains the tactical and creative force behind the operation. It's his program. It’s his board. We all know that.

But it was Pioli's job to help Belichick find the players who could flourish in that system, and he did it exceptionally well. The Pats will find somebody to take Pioli’s job (Nick Caserio), but they won’t find anybody better at doing it.

I don’t think it’s an exaggeration to say the Pats have just experienced the breakup of the greatest coach-personnel director pairing of this generation. Pioli was Belichick’s first hire after taking over in New England in 2000, and the program they inherited was a mess. Two years later, they had their first title. Nine seasons later, their trophy case shows three championships, six division titles, the NFL's only 16-0 record and the best winning percentage in all of professional sports since 2001.

Pioli rewrote the Pats’ scouting manual soon after taking the job back in 2000, and on the first page of the handbook he included a mission statement. It read:

"We want to build a big, strong, tough, smart, fast, disciplined football team that will consistently compete for a championship."

Nine years later, only two words apply: Mission accomplished.

Along the way, Pioli and Belichick were responsible for a host of incredible personnel decisions, headlined by the selection of Tom Brady in the sixth round in 2000. There were many other draft day and free agency successes along the way (Richard Seymour, Rodney Harrison, etc.), and while not everything they did worked out, Belichick and Pioli were productive when it really counted.

Just take the first round of the draft, where the money is big and the risks are enormous. You can make the argument that Belichick and Pioli never busted on a single first-rounder. Yes, Laurence Maroney and Ben Watson have frustrated us recently, but both have contributed in the past. They may be disappointments, but they aren't busts. The rest of the first-rounders are indisputable; they have either been key members of championship teams or key building blocks for the future – Seymour, Daniel Graham, Ty Warren, Vince Wilfork, Logan Mankins, Brandon Meriweather, Jerod Mayo.

By any measure, that's a great track record. If you don’t think so, then you don't understand the vagaries of the draft. Everyone screws up. Everyone takes the wrong guy from time to time. The “hit” rate even among first rounders isn't much better than 50 percent around the league. So if you can go eight straight years and never really have a first-round failure, that's remarkable.

This isn't to say that everything has been perfect around here the last few years. I would say that the biggest disappointment of Belichick and Pioli's tenure is the deterioration of the defense since 2004, a decline wrought by poor decisions in the draft, during free agency and at contract time. The secondary has been a particular problem. Since the productive offseason of 2003, when the Pats signed Harrison and drafted Asante Samuel and Eugene Wilson, nothing has really worked for them in the backfield, and now the team is essentially starting from scratch there.

There have been some other misfires as well. Did the Pats really need to draft so many tight ends (David Thomas, Garrett Mills, Andy Stokes, Spencer Nead, Jabari Holloway, Arther Love, Dave Stachelski)? And why was the second round such a problem (Adrian Klemm, Bethel Johnson, Marquise Hill, Chad Jackson)? There was a weird period where every veteran guard they signed seemed to retire a few weeks later (Joe Panos, Rich Tylski, Brandon Stai, etc.). And as it stands right now, the top of the 2006 draft is looking like a black hole (the first four picks: Maroney, Jackson, Thomas, Mills).

But those issues pale when compared to all the things Belichick and Pioli did right over the years.

Their greatest accomplishment, in my opinion, is the culture they created. The Pats have not only won, but they've won with teams that are routinely hard-working, tough, smart, versatile and selfless. We haven't seen those qualities just “flash” on occasion over the last nine years. They've been constants. They were apparent in 2001, when the Pats came out of the tunnel as a team in New Orleans and shocked the football establishment, and they were obvious again this season, when the Pats lost the best player in the sport and still “did their jobs” all the way to an 11-win season.

That will be the legacy of Belichick and Pioli's run. The three Vince Lombardi trophies are merely an affirmation that sometimes you can win the right way.

With a new era upon us, let's look back at the best and worst from the Belichick-Pioli marriage in New England. Send disagreements to mfelger@weei.com and we'll hash it out in Thursday's mailbag.

THE TWO PICKS THAT WERE SO GOOD, THEY ALMOST DON'T COUNT

1. Tom Brady, sixth round (No. 199 overall), 2000

2. Matt Cassel, seventh round (No. 230 overall), 2005

It's not fair to say these two selections were pure “luck.” Brady and Cassel obviously had qualities that Belichick values, including smarts and work ethic. Brady also produced in some big games at Michigan, and that clearly appealed to Belichick as well. The Pats didn't just close their eyes and pluck these two guys out of a hat. They scouted them and liked them. So there was some method there.

But let's be real: Brady, especially, and Cassel, to a lesser extent, were gifts from God. And the Pats know it. Pioli has a picture in his office reminding him that the round before selecting Brady, the Pats took a tight end out of Boise State by the name of Dave Stachelski, who was so ill-prepared for the NFL that he got homesick in training camp and was cut. The Pats also selected such luminaries as Adrian Klemm, J.R. Redmond, Greg Robinson-Randall, Jeff Marriott and Antwan Harris before taking Brady that draft. In other words, they caught lightning in a bottle. Ditto for Cassel. For this exercise, we'll take them off the table.

BEST “REAL” DRAFT PICKS

1. Richard Seymour, first round (No. 6 overall), 2001

In my opinion, this was the single most important draft pick this decade. The Pats were coming off a 5-11 year and had given up their first-rounder the year before to pry Belichick away from the Jets. They had needs across the board. Given where they were and the bonus money they’d be spending, it was a pick that the franchise absolutely HAD to have. And Belichick/Pioli delivered. There were seven defensive linemen drafted in the top 13 picks that year (Gerard Warren, Justin Smith, Seymour, Andre Carter, Jamal Reynolds, Damoine Lewis and Marcus Stroud) – and the Pats came away with the Hall of Famer. Remember the cries for a receiver (David Terrell/Koren Robinson) that year? The selection of Seymour was the first in a long line of tone-deaf decisions by the Pats that proved to be spot on.

2. Vince Wilfork, first round (No. 21 overall), 2004

This was a gift from the rest of the league that Belichick and Pioli gladly accepted. You can't run a 3-4 defense without a nose tackle, and the Pats got a franchise guy in the 20s.

3. Dan Koppen, fifth round (No. 164 overall), 2003

Damien Woody was entering his last year and was on his way out. So the Pats targeted a replacement and hit pay dirt from the bottom half of the draft. The Boston College product was a starter at center by Week 2 of his rookie year and has been there ever since.

4. Asante Samuel, fourth round (No. 120 overall), 2003

The vast majority of big-play, franchise corners in the NFL are drafted in the first round. The Pats found theirs in the fourth.

5. Deion Branch, second round (No. 65 overall), 2002

The draftniks cried “reach” when the Pats made this selection. Three seasons later, Branch was reaching for his second title and a Super Bowl MVP trophy.

Honorable mention: Jerod Mayo (first round, No. 10 overall, 2008) – like the Seymour pick, the Pats simply HAD to come out of that selection with a stud on defense, and it looks like they did. Stephen Gostkowski (fourth round, No. 118 overall, 2006) – Pats needed a kicker and they got a good one on their first attempt. Matt Light (second round, No. 48 overall, 2001) – not a spectacular player, but will probably be an every-game starter for close to a decade. That’s good value. David Givens (seventh round, No. 253 overall, 2002) – a bit of a fluke. Remember, this was a pick the Pats kept passing on as they squared away Givens’ medical reports.

WORST DRAFT PICKS

1. Chad Jackson, second round (No. 36 overall), 2006

The Pats were warned about the knuckle-headed Florida receiver, but they ignored the reports. Instead, they floated stories about Jackson's alleged football intelligence, which turned out to be nonexistent. You'd figure Belichick's buddy Urban Meyer would have given him a better hookup.

2. Bethel Johnson, second round (No. 45 overall), 2003

This is what happens when you draft on combine results. Johnson made a handful of plays (mostly on kick returns) over three seasons and was gone.

3. Brock Williams, third round (No. 86 overall), 2001

Bet you don't even remember him. Knee and maturity problems made the cornerback a non-factor from Day One.

4. Adrian Klemm, second round (No. 46 overall), 2000

The first-ever pick by Belichick and Pioli in New England was hardly an auspicious debut.

5. Laurence Maroney, first round (No. 21 overall), 2006

The linchpin of what is looking like a bad draft. The first six picks that year were on offense (Maroney, Jackson, Thomas, Mills, Gostkowski, Ryan O'Callaghan), and only one of those selections, Gostkowski, has provided value. This draft has ended up hurting the Pats on both sides of the ball because defense was ignored (LeKevin Smith, taken in the sixth round, is the only defensive guy left from that class).

Honorable mention: Benjamin Watson (first round, No. 32 overall, 2004) – falls just below bust status. Marquise Hill (second round, No. 63 overall, 2004) – a good man. May he rest in peace. Guss Scott (third round, No. 63 overall, 2004) – the secondary would look a lot different today if he or Dexter Reid, another safety taken in the fourth round that year, could play. Rohan Davey (fourth round, No. 117 overall, 2002) – the magic dust sprinkled on Brady and Cassel didn’t stick to him.

BEST FREE AGENT SIGNINGS

1. Rodney Harrison, 2003

As responsible as anyone for the titles in 2003 and 2004.

2. Mike Vrabel, 2001

A great scouting job by the Pats on this one. Vrabel, a backup in Pittsburgh, was a perfect fit in the Pats’ 3-4 defense because of  his size, versatility and intelligence. He'll go down as one of the poster boys for this run.

3. Bryan Cox, 2001

Gave the Pats exactly what they needed at the time: Toughness and attitude.

4. Adalius Thomas, 2007

Injuries have cut into his production. But the Pats deserve credit for being bold and aggressive in brining in another guy who is perfect for their system. Where Vrabel was a bargain, Thomas cost them dearly ($20 million guaranteed up front). He's still a stud.

5. Bobby Hamilton, 2000

A forgotten man. The castoff from the Jets came here with little fanfare in 2000 and wound up leading the NFL in tackles among defensive linemen. He went on to be a key member of two Super Bowl titles. A great Patriot.

Honorable mention: Joe Andruzzi, 2000; Jermaine Wiggins, 2000; Larry Izzo, 2001; David Patten, 2001; Roman Phifer, 2001; Anthony Pleasant, 2001; Antowain Smith, 2001; Terrell Buckley, 2001; Christian Fauria, 2002; Don Davis, 2003; Keith Traylor, 2004; Heath Evans, 2005; Junior Seau, 2006; Donte Stallworth, 2007; Kelley Washington, 2007; Sammy Morris, 2007.

WORST FREE AGENT SIGNINGS

1. Monty Beisel/Chad Brown, 2005

The Pats went into an important transition year at linebacker after Ted Johnson retired, Roman Phifer moved on and Tedy Bruschi suffered a stroke. And Pioli and Belichick simply failed in finding adequate replacements. By midway through the year, Bruschi and Vrabel were starting inside and Beisel and Brown were on the bench.

2. Fernando Bryant/Deltha O’Neal, 2008

You can understand the Patriots not wanting to pay Samuel $20 million up front. But does that mean they had to replace him with one guy cut by the Lions (Bryant) and another guy cut by the Bengals (O’Neal)? Atrocious.

3. Donald Hayes, 2002

The receiver from Carolina was supposed to be Brady's “size” target for years to come. Instead, he couldn't figure out the offense and was gone in a year.

4. Reche Caldwell, 2006

Not that Caldwell was awful, as he wound up leading the Pats in receiving his one year in New England (61 catches). It’s what he represented, which was an abandonment of Brady. The Pats quickly corrected the problem the next year.

5. Tyrone Poole, 2003

It's hard to call Poole a total bust since he was an instrumental guy during the Pats’ 2003 championship season. But Poole had to be coaxed into reporting that year, and then he basically bailed on the team the next two seasons.

Honorable mention: Antonio Langham, 2000; Eric Bjornson, 2000; Victor Green, 2002; Steve Martin, 2002; Cam Cleeland, 2002; J.J. Stokes, 2003; Rodney Bailey, 2004; Dana Stubblefield, 2004; Eric Warfield, 2005; Tebucky Jones, 2006; Marcus Pollard, 2008.

BEST TRADES

1. Randy Moss, 2007

For a fourth. No elaboration necessary.

2. Wes Welker, 2007

The Pats would have claimed the slot receiver as a restricted free agent if a deal hadn't been worked out, with the Pats sending Miami second- and seventh-round picks. The Dolphins could have commanded a higher price by giving Welker a high, first-round tender for just over $1 million for one season, and the Pats may not have bitten. That's one of the many reasons why Bill Parcells is currently running the show in South Florida.

3. Ted Washington, 2003.

Big nose tackle came from Chicago for a fourth-rounder and immediately turned around the run defense.

4. Corey Dillon, 2004

Came from Cincinnati for a second-rounder. For one season he was brilliant. For the next two he went back to being Corey Dillon.

5. Terry Glenn to Green Bay, 2002

Instead of just dumping the immature (at the time) Glenn for nothing, the Pats sent him to the Packers for conditional draft picks, which ended up being a fourth-rounder in 2002 and a fourth in 2003. The former was used to select Jarvis Green; the latter was used in a package that became Samuel.

Honorable mention: Drew Bledsoe to Buffalo for a first-round pick in 2002 was a bit of a no-brainer. They used the pick to select Ty Warren the next season. Franchised safety Tebucky Jones was sent to New Orleans for third- and seventh-round picks in 2003, which the Pats used to trade up and get Eugene Wilson in the second round that draft. In 2003, they made another deal that falls in the no-brainer category, sending Miami a 2003 third for a 2004 second, which they used to acquire Dillon.

WORST TRADES

1. Duane Starks, 2005

The corner with the Super Bowl pedigree (Baltimore, 2000) was a disaster from the start and didn't make it through the season. He cost the Pats a third-round pick in addition to a guaranteed salary in excess of $3 million. A total waste.

2. Chad Jackson, 2006

What made the Jackson pick so bad was that the Pats traded up to do it, sending the Packers a third-round pick to go from No. 52 to No. 36. The Packers sat at 52 and took receiver Greg Jennings, who has been great.

3. Doug Gabriel, 2006

Only cost the Pats a fifth-rounder, but a debacle nonetheless.

4. Andre Davis, 2005

Not nearly as bad as Gabriel, but still part of the problem at receiver during that era, not the solution.

5. Deion Branch to Seattle, 2006

I know most of you disagree with me on this. The Pats got a first-rounder from the Seahawks in 2007, which wasn't bad value. The Pats used it to select Brandon Meriweather, who has had a hot-and-cold two years in New England. I just think Brady and the offense were so good with Branch in the lineup, and the unit took a giant step backwards after he left. To me, it wasn’t worth it.

BEST CONTRACT DECISIONS (CUTS/FREE AGENT DEPARTURES)

1. Lawyer Milloy, 2003

Belichick was way ahead of the curve on the franchise safety, and the transition to Harrison, while rocky at first, turned into a huge upgrade.

2. Damien Woody, 2004

Pats weren’t about to bite (pun intended) on that contract or those weight issues. Woody made a killing in Detroit and the Pats got better with Koppen.

3. David Givens, 2006

The Pats decided not pay their No. 2 receiver, and then he proceeded to completely fall apart. Good timing.

4. Chad Eaton, 2001

Everybody loved the big-talking nose tackle, but if the Pats had paid him what he wanted, they wouldn't have had the cap room to completely redo the roster that spring. The Eaton money was the currency they used to win their first Super Bowl.

5. Ted Washington, 2004

Keith Traylor was cheaper and, between he and Wilfork, the Pats were able to keep the middle plugged en route to another title.

Honorable mention: Tebucky Jones, 2003; Joe Andruzzi, 2005; Willie McGinest, 2005; Dan Graham, 2006.

WORST CONTRACT DECISIONS

1. Asante Samuel, 2008

His loss cost the Pats a playoff berth (at least) this year. He has proven to be worth the money; big-play guys don't grow on trees.

2. Deion Branch, 2006

Would have been worth the money playing next to Brady.

3. Corey Dillon, 2005

Dillon's contract extension with the Pats signed after his record 2004 season was unnecessary since he already had a year left on his existing deal. It brought out the bad Corey, both on the field and off.

4. Adam Vinatieri, 2006

Gostkowski has been great and Vinatieri is clearly on the tail end of his career, but Adam had enough left in the tank to give the Pats at least a few more years, something he proved during the Colts’ Super Bowl run in 2006. Remember, kickers are the cheapest players on the field.

5. Richard Seymour, 2006

Not a good contract for the Pats. Seymour hasn't been the same guy after signing his massive extension in 2006. And at only four years in length, Seymour is again eligible for free agency after the 2009 season. He’s one of the few players to have gotten the better of the Pats at the negotiating table.

Honorable mention: Ty Law, 2005. He was productive for several more seasons after his release, just as he said he would be. The Pats could have used him.

Michael Felger can be seen nightly on Comcast Sportsnet and is a regular contributor for WEEI.com. He can be reached at mfelger@weei.com.