Where Does Gregg Williams Fit Into Saints History?

The amount of mileage he got out of a defense that really didn't have elite talent outside of Vilma, Greer, and Sharper is actually crazy when you sit down and look at it.

Will Smith was at the end of his career and no longer the force he used to be.
Charles Grant? LOL.
Sedrick Ellis was basically a bust.
Hargrove was talented but troubled.
Bobby McCray was a situational roleplayer.

Vilma was genuinely elite.
Fujita was average to above average, but definitely not in the league's elite.
Shanle... absolutely no one will call him elite, great, or even good.

Darren Sharper had one final gallon of elite gas in the tank.
Greer was genuinely elite.
Porter was as likely to lose the game as he was to win it. 2009 he won more than he lost gambling, but when you look at his career, he was not good.
Roman Harper was a downhill in the box strong safety (an extinct position) with zero pass coverage awareness.
Malcolm Jenkins was a rookie.

Gregg Williams was able to turn that into one of the scariest defenses in the league for exactly one season, which honestly was one season more than they had any right of being good.

He called a brilliant 2009 season and constantly had his players, including guys like McKenzie and McAllister signed off the streets balling out of their minds.

It is perfectly fine to hate him and hope he falls down a flight of stairs covered in legos, but you gotta give him credit where it is due, and 2009 was basically his perfect year.
I generally agree with your analysis. Just as I had problems with Haslett but will still salute him for our first playoff win, I'll do the same for Williams being a part of that SB team.

And remember, Sharper was only really elite for the first 2/3 of the season. Once his knee started acting up, he looked very ordinary and the only play of note he made in the postseason was when a fumble fell in his lap vs. AZ (someone else forced it). And we held Peyton & co. to under 20 points in the SB.

As for lighting in a bottle, yeah, turnovers are always somewhat luck dependent (where a fumble or a tipped pass bounces, a QB under or overthrowing an open WR, a WR/QB getting signals crossed and a pass going straight to a DB). Porter's postseason was a great example (the MIN INT was b/c Favre brain farted and threw across his body instead of to Bernard Berrian who was right in front of him on the sideline at the 30, but the SB INT was a great read). Still, defense wasn't the only lightning in a bottle aspect of that team. Hartley was not a reliable kicker in his NFL career. But he was money in that postseason and set a record for only kicker to make 3 field goals of 45+ yards in the same Super Bowl.