I thought I had posted another reply on this topic, but I don't see it.
the reason games run slow is because of filtering. turn filtering off, games should run fine.
before schtruck implemented the option for using multiple CPU cores, filtering was almost useless because it made games run too slow. but with the ability to use multiple cores, filtering became much more possible. For me, using multiple cores makes games run choppy, as if there is a lot of frame skip, so I never use it. I think that issue is part of the major problem with the 11.30-11.33 updates - it was same issue, just made more dramatic.
with the continued improvements schtruck has made, games almost run fast enough that you can use filtering even with 'forced monocore' turned on.