The main problem with Blizzard_CompactRaidFrames in most of Cataclysm was the fact it was tainting itself while trying to update in combat. There are problems in Blizzard's code, they are not the holy grail of programming by any means.
I forgot many specific reasons, but Blizzard has been known to randomly blame addons in this way. In this specific occasion, when removing/disabling said addon, it just blames the next one down in the list.