B-spec to me, in the way it's implemented in GT5, is just boring beyond belief.
Yes it might be clever and complicated and require smart decisions and instuctions (which I all already put into practice since I'm at level 40 with all events golded, all trophies and 3 level 40 Bobs so I know how to use it but will never touch the offline mode again and thankfully don't 'have' to) but since it isn't integrated into A-spec (like it worked perfectly fine in GT4) and you can't speed it up (again how it was in GT4) it basically is the game being played by the game which to me is indeed a waste of time and energy.
Now with remote racing you receive money by other players letting the game play the game and although it might be an easy moneymaker for many people, the only time I use remote racing is to return the favour whilst simultaneously recharging my controller....
Some might like it but there's no fun in using B-spec for me (I only used it to acquire the prize cars, and yes, for game completion, etc.).
It might be different if it were truly something completely different than being basically a real time replay with extra data being displayed, for example a sort of first person mode where you could walk around the pit-area as the team manager giving instructions to mechanics, get info from different engineers and decide which advice to take or make up your own tactics, walk to the monitor to follow the race, talk to the driver, etc., etc.
If B-spec remains a separate mode, then make it something completely different, fun and interesting to experience and make it more worthwhile than simply being an automated version of A-spec which it is to me despite all the apparant cleverness behind it.