I mean over the 2010 off season he fixed his service arm so that during his trophy pose his right arm isnt straight as it was, it has a 90 degree bend. Its one of the main things that attributed to his Australian Open win...
i actually think you SHOULD limit the stuff in fairmode to 90% (although you might have to lower serve to cope with the speed loss), as it will force people to be more creative and will increase the type of playing styles you will see online as opposed to the majority of defenders and bashers...