Dean Oliver actually uses a statistical formula based on standard deviation to prove the percent chance that a team will win a game! Unfortunately, Dean has not done nearly as much as Ken Pomeroy in terms of figuring out how to adjust statistics for quality of opponents. So currently I am working on a system that turns Kenpom's predictions into chance of win.
Dean Oliver's formula is as follows:
Win%=NormsDist(Point Margin/Standard Deviation of Point Margin)
so if I perhaps used Kenpom's predictions--
Chance of Win%=Normsdist(Predicted Point Margin/Standard Deviation of Actual Minus Predicted Point Margins of both Teams)
This gives us a good number (for example, 2008-2009 North Carolina posts an on-season 96.5%, whereas the Log5 formula puts them at 97.7%) -- but I am still unable to adjust for opponents' inconsistency. Oh well -- it's definitely a step in the right direction!