Let me try to specify.
Shade is a proponent of Sodium R lipoic acid and his research largely matches the numerous peer reviewed papers I have read on R lipoic. Cutler is adamant to not use RLA at all, and insists and has for decades to use ALA because ALA is where all the research is at.
ALA is a racemate which as you say is 50% biologically inactive in terms of its ability to be absorbed properly for primary effect on cells, especially mitochondria and the important roles that lipoic plays in transcription of DNA. But what I at least speculate, is that in some way this is a good thing based on Cutler's argument that ALA should be used as a chelation agent that effects equilibrium in the body, thus observing the half life and deriving specific pharmaceutical effects from this indirect effect of ALA as opposed to direct cellular effect. . .half of it is inactive, but that half still mobilizes and attaches to mercury... and Cutler is correct that free RLA (the kind not sold as sodium RLA) is very unstable. In fact it will degrade on you if you don't keep it well stored, and is generally not something that dissolves well in liquid, so its usually a tablet.
With ALA it degrades to DHLA, but specifically the (R)+DHLA and (S)-DHLA both which move mercury around. But RLA gets metabolized more, used more by the body. So I speculate that this slows down its ability to actually persist and mobilize in the body like the S fraction.
On the other hand there are a lot of reasons why taking a 'critical threshold' of RLA is good, generally, especially for people who don't have mercury poisoning. Shade doesn't use very large doses of RLA and is insistent that it will not cause redistribution. But it is a bit unnerving. I've personally tried to take RLA in single large doses without any issue, but I've noticed redistribution symptoms when I took it in frequent doses and missed a dose or took it slightly too late or absorbed it poorly because of a full stomach of food.
Come to think of it, the safest bet would be to apply a transdermal application of lipoic every 2 hours or 2.5 hours to be honest....its a pain at first. I've tried RLA suppositories, and that is a hassle as well.
There are of course even more reasons why Cutler probably hates RLA, but none of them I can even begin to speculate on, as he seems quite hush about it.
I'm pretty sure RLA affects me much less than ALA though. I get some horrible side effects from ALA in particular. And I tolerate much smaller doses. But based on what Cutler says, and on the papers I've read, I'm still going to likely shoot for 15 mg of ALA each dose, and perhaps add RLA to it, at least as long as the ALA doesn't beat me up too much. If I get desperate enough I might give up on ALA all together. But the science I just mentioned is what I believe to be true.