After tons of retries, I managed to get Anathem as fast as possible, at least on PRO playing on GCN. I actually go so fast during the middle of the level that the RTA strat barely works and requires me to wait for a few frames for the lawyer to arrive in the correct spot, so I can get a key. If I rush out any faster, I'll have to run to his corpse, which wastes time. This is still a few seconds slower than the RTA due to the fact that RTA plays on Normal, so he gets access to a silenced pistol, instead of needing to kill the first guard with the fiber wire.
Also, I saved 87 frames on the tutorial thanks to a trick pointed out to me by Cooljay.