It isn't hard to implement as GT4 already had a fast forward function for B-spec, PD just decided to remove it for whatever reason.
Guess they wanted B-spec to be taken seriously as a gameplay element in itself instead of the easy-money route it was in GT4 although I'm getting really bored by it now, it's fun for a while pretending to be Norbert Haug, Jean Todt or even good old, ahem, Flavio Briatore (considering some of my B-spec monkeys crashed after my instructions..........) but I'd rather be behind the wheel myself thank you very much.
Sure you can watch the telly or do other stuff whilst B-spec Bob (and his cohorts) are racing but then again, why not fast forward it when you don't pay attention to it anyway?
On a sidenote, is the X1 (excuse me, X2010) available at B-spec level 30 or 35, hear conflicting info about this?
(The only reason I do B-spec is game progression and price cars, not because it's any fun)