Uga looks good, but should they and Ala both be considered for the semis? If NCSU loses only to CU, wouldn't they be in the same spot?

Given parity, it doesn't seem like a 4 team playoff captures the 4 no-question best teams in the US (an argument against that might be that the ACCCG, etc. takes care of the other top teams, except when the 2 division winners are not necessarily the 2 best teams in a given conference.)