I think that the biggest problem with ending the brand split is making it so it doesn't feel like you are just rotating the world title.
With... Cena, HHH, HBK, Taker, Orton, Batista, Jericho, Edge, Rey Mysterio how could you occupy them all on the same brand without things getting stale?
You get Batista losing his feud with Cena... but then winning the next feud with HHH. You'd never get Batista losing two or three feuds in a row. Or you'd just get alot of draw feuds (one win each over two PPV's).
Im all for better programming.... but just ending the split doesn't guarentee better programming. I'd be happier to have a dominant brand. Have all the big names on RAW with say One Big name with alot of prospects. Let Morrsion, Kingston & Miz have World title runs and see what they can do even if its not on RAW.
Plus how could guys like Sheamus, Morrison, McIntrye, Kingston, Dibiase & Rhodes, Miz etc become main eventers? They would really struggle to dominate a brand with all those massive names.