I just read an article about some bonus keys on the iPad's split keyboard. Obviously this seems like a great idea to prevent a usability issue from even happening. It seems like this could backfire just as easily though.
I don't think there is any inline help/documentation about this feature so I have to wonder if it (or other ideas like it) could backfire. Are there any good rules for taking the observation that someone at Apple had ("Hey, those people don't type exactly like how we split the keyboard") to a subtly hidden usability improvement like this compared to a menu option for 2-3 different versions of a split keyboard?