Offensive development so far.....

To what degree can Paul Johnson's offense now be called proven at the BCS level?

I'm not sure, but here are GT's offensive numbers vs. the 7 BCS league teams we have played in 2008 and they're not too bad:

Rushing: 250.4 YPG vs. teams giving up 114.1 YPG to their other opponents.
Total offense: 353.7 YPG vs. teams giving up 298.7 YPG to their other opponents.