Ahh, I'm not the only one that experienced these kinds of falling through moments eh? Interesting.
I was patched to the max also.
Howver I think I had more trouble with getting stuck in walls (in Balmora specifically) and being able to see through them or above them when it happened.
It would most often happen when I was jumping or bumping into walls, either during combat or just from sheer spelunking about. I'd often just jump up onto tables and beds to get my acrobatics up faster.
It happened in a couple of tombs also.
Sometimes I could get out, but every now and again I'd have to reload.