This is the relevant bit from my testing before that I found in this thread:
As compared to this:
This was pretty aggressive PCA-ing as you can see. I don’t know why I stopped at 9d as it was going up from there (say vs 20d), but I think I was comparing 196d->9d vs “raw” 21d or something along those lines. So going from 21d->20d doesn’t make much sense.