@oristarA,
You are right, that sentence is a bit of a stinker.
Quote:...not on the diagnoses made by the alienists at the trials, but on replies made by them to these test questions, about which they are little more capable of judging, distinguished authorities though they may be, than anyone else.
not on the diagnoses made by the alienists..., but on replies made by them (the alienists)...
... about which they (the alienists) are little more capable of judging, distinguished authorities though they (the alienists) may be, than anyone else.
(by the way, this is the first time I have seen the word alienist, I believe)