One shouldn't blame a game for his lack of competence.DS2 + Rubber band + Motegi Speedway (and the older GT3 equivalent) = Easy win.
I've actually found that your laptimes go down for the GT4 endurance race at the track if you just start wall-riding the whole track compared to actually taking the corners on green tires (and goes with the bonus that you never need to pit). The damage engine will likely make it so it isn't worth exploiting (assuming it is implemented in a way that takes such into account), but the problem would still be there.