Here, it is shown 90 of 960 positions involve having to move a rook on 1 side in order to castle on the other side (unless the rook is somehow captured or something). These 90 positions come from 18 rearrangements/permutations/combinations/whatever from each of 5 groups of starting positions (SPs)
Based on the Sesse evals for the 960 SPs (see here also) or based on other similar sources (such as practical instead of theoretical statistics like win rate eg this (computer chess) [again see here]), what is white's increased advantage in chess90 compared to chess870?
Note 1: This can't be vacuous. If white actually has a bigger advantage in chess870 compared to chess90, then the answer is simply negative.
Note 2: I'm answering below for the sesse evals. I have yet to answer or receive an answer for the computer chess statistics.