Quick? He has coached 22 years and has a runner up and one other final four. 12 of his 22 years he has 6-8 wins, including all 4 with the Rams. His best attribute is convincing owners he is a year or two away. And his style of stout D and running game is archaic in the NFL now. He promoted his TE coach to be OC this year. They have the worst QB/WR combo in the league after all those picks from the Redskins, not from bad luck. Plus I hate the porn stache.
You need to do more research. You need to do research as to "why" he's generally been a .500 coach. First, some historical reference.
In general if a head coach wins at a percentage of >.600 (and has a fair length career) that they are considered coaching legends. Even guys like Shula won .676 of the time. Fisher is at .521. That may sound low but out of head coaches who have 50 wins or more he's 65th of ALL TIME. Guys like Coughlin, Vermeil, Gruden, Billick, Jimmy Johnson, Kubiak, Shell, Pete Carroll, Wade Phillips, Marvin Lewis, Green, Ditka, Mora, Fox, Shanahan, Reeves, Parcels.....are all within a few tenths (+/-) win percentage of Fisher.
What you will also notice is there are some coaches in this list who have won SB's while Fisher has not. Of those, who was their QB and/or who was the organization they were with? Would Johnson have won 2 SB's without Aikman/Smith?.....and why was he unsuccessful in Miami? Would Carroll have won without Russell/Lynch? Shanahan without Davis/Elway?
And what organization are they with? Belichick was fired from a miserable term in Cleveland.....before he was hired in NE. This matters because in the NFL, the coaches don't shop for the groceries. For example, in college the coaches choose the player, recruit them, then coach them. In the NFL, the coaches are given players and forced to do the best. The best organizations will work together and make great rosters.
Now, if you look at Fisher's seasons more closely. When he has a good roster and good QB play, he makes playoff runs. When he doesn't have those things he's good enough to get to get 7-9 wins. Now, I can tell you without a doubt that the front office in Tennessee wasn't stellar about getting Fisher what he needed. McNair was probably one of the most WR starved QB's during the 2000's. And Fisher has also had rejects like Vince Young forced on him by ownership.
Now, on to the Rams. They have built a really nice defense but there's no question that they are QB/WR starved.
None of this means Fisher is Hall of Fame walking, but it does mean he's a really good coach who really hasn't been put in the best position to succeed. What you have seen the last few yrs in St Louis is not a result of poor coaching. It's a result of good coaching and so-so roster talent.
