Huh. I'm a little confused about the whole Buu thing. How could the fat Kai's power have been transferred to Kid Buu during the split? Fat Buu only existed due to Kid Buu absorbing the fat Kai. During the split, Evil Buu and Good Buu were created, and since Good Buu was weaker, it's my understanding that Good Buu only contained the fat Kai's power (which was said to influence Buu and granted him some semblance of a conscience, thereby making him weaker), while Evil Buu contained the power of the other Kais. After they merged again, Super Buu was created despite being made of the same power and absorptions due to the fat Kai's influence being suppressed this time. When Buu reverted back to Kid Buu, he was supposed to be in his pure, original state, with absolutely no one absorbed. That's why Good Buu existed, since that form contained the fat Kai's power. (it never stated what happened to all the other power. It seems like it was just misplaced -or forgotten about- ) Without the fat Kai's power, that version of Buu (both Fat and Good) shouldn't exist, and if Kid Buu had the fat Kai's power, he should have turned back into fat Buu himself, since that's how he came to be in the first place. So Uub, who was a reincarnated Kid Buu, shouldn't have fat Kai's power at all.
But then I'm sure I'm just missing something.