The whole issue is making me think of swimming. Most people would accept that a swimming teacher or class is helpful or even essential and yet most runners are self taught. OK, so maybe running is very natural and we 'just do it', but over extended distances many people approach their limits and maybe more coaching should be seen as the norm?
I suppose one problem is that the biomechanics of running are controversial (witness the barefoot movement) and for every supporter of Q-angle you could find a coach or therapist that thinks such concepts are unhelpful, or even fanciful! In general there appears to be far more agreement amongst the swimming community as to what is effective or harmful.