I gave it a try and it's as pointless as the official announcement led me to believe. They have implemented it in a way that makes me wonder why anyone wouldn't rather drive the car themselves. It's not like it's easier for new/bad drivers to provide
all these instructions than it is to overcome the not so steep learning curve of beating A-Spec opponents.
Why not keep it as it was in GT5 but without the separate game mode to play through? This would mean that we would have a number of AI drivers to develop, limited instructions to give during races, and the now simpler integration of A-Spec and B-Spec into the exact same events. Instead of enabling players to remote control a driver they don't even "get to know", they could have spent the time making the driver development aspect a bit more interesting. B-Spec doesn't even need the AI overhaul as much as A-Spec does because every B-Spec driver will always be in the same boat, so I don't get why they felt the need to bring up the AI in their latest pitstop blog entry. I figure they brought it up to explain the new approach. Finally, it was nice to remote race the drivers of you PSN friends in GT5 and get the favor returned. Not only did it provide a boost every now and then but it also enhanced the community aspect.
At this point I wish they had never promised B-Spec for GT6 because it really is completely pointless now.