I was watching UltimaShadow's solo Omega Weapon battle:
YouTube - Waka Weapon part 1
YouTube - Waka Weapon part 2
And I noticed that he wasn't landing perfect Renzokukens. I also noticed he got a whole lot more Lion Hearts than I normally would, so I wonder whether purposely missing the trigger on a few Renzokuken hits affects "randomness" in getting either one of Rough Divide, Fated Circle, Blasting Zone or Lion Heart?
BTW: I kind of remember from the last time I played the game (about 2 years ago, mind you) that I was coming up with Lion Heart with almost every limit break when Ultimecia used the 'reduce everyone to 1 HP' move. I'm really not sure. If someone could confirm this too, that'd be a handy bonus.