I don't think Bogans is intended to be a starter, but is in there as a stop gap measure filling in for injuries and unexpected mediocrity, so that eventually, he'll slide back to his natural role player position, coming off the bench, and be a good addition to the roster. He had a stretch of over-achievement, playing above his normal abilities, and the Spurs tried to ride it for too long, making him look poor as he regressed to normal. He'll look good again when he goes back to his natural role. Probably.