NFL Overtimes

There's a lot of animosity in the local media here in Philly directed toward Donovan McNabb for not knowing that NFL games can end in ties.  Presumably, McNabb might have played differently if he'd known that games can end in ties but I don't want to weigh in on that debate. Instead, I'd rather ask why the NFL hasn't converted to the college system? NFL overtimes don't grant equal possessions to each team (which has been a problem for a long time), and the sudden death format is unfair because of this.

College overtime games can sometimes have ridiculous 70-69 scores if there are multiple overtimes and the league probably doesn't want to invalidate old touchdown, yardage and scoring records, but there are ways to ensure the scoring doesn't get blown out of proportion in "equal possession" overtimes. 

The easiest way to do this is for the NFL to adopt the college model but simply adjust it.  NFL teams should begin the 1st overtime with equal possessions from the 20. Then from the 30. Then from the 40. Then from the 50. The second overtime should, like college, require a two-point conversion if the team scores a touchdown.  It's still possible overtime games could end up with high scores, but the chances under this kind of system would be greatly diminished while satisfying the "fairness" problem of the current overtime system, providing fans a much more exciting game and also eliminating ties (something I think American sports fans hate more than losses).  

Update: Apparently McNabb also didn't know that playoff games and SuperBowls don't end in ties.  Which makes me wonder what he thought would have happened then?  Did he think teams that end up tied in a playoff game both advance?  How miserable would that be for the poor third team that has to play the other two??? Sheesh...