In a recent column Lowell Cohn wrote, "Mike Singletary had the same players with a few exceptions and couldn't deliver". That's a typical media opinion, that Harbaugh, using almost or mostly the same players as Singletary had, was solely responsible for the 49ers stunning success. You here the theme over and over, by sportswriters, on TV and on sports talk radio. It has become the conventional wisdom.
There is one problem with it - it's dead wrong. It ignores a major story, a significant accomplishment of the 2011 49ers - the rebuilding of the defense by Trent Baalke. When you look at the changes in defensive player personnel from 2010 to 2011 in detail the scope of the makeover that Baalke orchestrated becomes clear. It wasn't just "a few exceptions" as Cohn said, but a whole lot of exceptions, a total rebuild.
Of the 13 defensive positions positions (the starting 11 plus a situational pass rusher and nickel back), nine of them had new players. That's a major transformation. Baalke did it by by moving backups into starting roles - Brooks replaced Lawson at outside linebacker, Bowman replaced Spikes at inside linebacker, Sopoaga moved from defensive end (replaced by backup Ray McDonald) to replace Franklin at nose tackle. Brown replaced Spencer at cornerback. Baakle acquired quality free agents - Whitner at strong safety and Rogers at cornerback. Baakle drafted Aldon Smith as a pass rusher and Culliver as a nickel back. Every one of these moves was an upgrade at the position. Only Goldson and Willis and Haralson and Justin Smith werre carry-overs at their position from 2010. Vic Fangio is a fine defensive coordinator, but he could not have achieved the results he did using 2010's players.
This in no way diminishes the job Harbaugh and his staff did; they deserve all the credit they have received. But Baakle deserves equal credit for what he accomplished. Together they engineered one of the most remarkable turnarounds in NFL history. Neither could have done it without the other.