Because they are traumatized and myopic and get suckered in by the "Mastermind" nickname. Because they haven't watched every bronco game in the last 20 yrs and don't realize that Shanny wasn't the only reason we won two superbowls. Don't get me wrong, he played his part and I'm grateful for the most gratifying sports experience in my lifetime. I just think John Elway, Terrell Davis and steroids are the main reasons Shanny gets all the hype. Sure his schemes were cutting edge circa 1996, but I'm willing to bet he doesn't take the Redskins to the superbowl - Cowboys maybe. Even if his name allows him to pick and choose his recruits I'm not sure he picks the right ones, remember Willie Middlebrooks, Marcus Nash, Ashley Lelie...
Not trying to be a downer, just playing devil's advocate