McKinnon has had a chequered career at best and I have a sneaking suspicion that you could chart his levels of success to who the coach was. It seems to me he has responded to some coaches a lot better than others. That doesn't mean the coaches were good or poor but should highlight to us that these players aren't robots and how sometimes we might be critical of players when its hard for them to perform when they aren't happy.
I liken it to school for me. I would say you could chart my schooling success to certain teachers. My best grades weren't necessarily achieved in certain subjects but whether I responded well to a the teacher or not.
Some coaches are great and seem to have a great knack out of getting the best out of their players, something Des seems to be excellent at. Its probably more important than any tactical knowledge and should also help in recruitment of juniors, especially if they believe they will be a better player for going to your club.
I guess the lesson is that we might judge players too quickly and label them as hopeless when in reality all they might need in a change in footy scenery to go from terrible to at least passable if not a star NRL performer.