Thanks for the reply. I know I can seperate the mesh into two but thats sort of behind in todays market. As long as I can modify the bones rotation while still having the keyframes effect it i'm happy (I don't mind doing the math). That way I can achive a huge amount of animations that will blend seamlessly.

Just to be clear if I add 10deg to a bone does it add it to its current rotation that is set by the keyframes or would the keyframes stop effecting the bone all together?