Ok, I have his Jan. 29 .plan update in front of me. It sure looks like Carmack has reduced quality code paths at his disposal, but where exactly does he say that he's indeed using
them? From this statement, it doesn't sound like he's using them:
so when Nvidia runs fragment programs, they are at a higher precision than ATI's, which is some justification for the slower speed. Nvidia assures me that there is a lot of room for improving the fragment program performance with improved driver compiler technology.
Sounds to me like he's holding out hope for said increases. I suppose we'll have to wait until the game is closer to going gold before we'll know for sure if said other code paths have been used.