Abso-tootly! in fact Cos was on Leno not long ago and did his old routine along with telling the story. http://www.fquick.com/videos/viewvideo.php?id=4967#
Here's a quote from Wikipedia "Another non-competition 427 roadster, CSX3303, was converted and given to Shelby's close friend, Bill Cosby. Cosby attempted to drive the super-fast Cobra, but had issues with keeping it under control. This was humorously documented in Cosby's album titled "Bill Cosby, 200 M.P.H.".
As well as corroboration from the "How Stuff Works" website "Shelby actually created two Super Snakes. The other was originally sold to comedian Bill Cosby. Cosby returned the car after just one drive, using the fright-inducing experience as material on his comedy album, "200 M.P.H.," said Harley E. Cluxton, a collector who owned the Super Snake sold at Saturday's auction. Writing on the Barrett-Jackson site, Cluxton said Cosby's Super Snake was later wrecked in a road accident in which its driver was killed.".
Besides, I'm not smart enough to make this stuff up! Remember, this was loooong before Bill got his doctorate. At the time he was still Robert's Culp "trainer" in I Spy.