An interesting and balanced reply. I take it you have some experience of the profession then?
A few days late to this arguement granted but my view from both sides of the fence is....
I've taught kids from one of the most deprived wards in Kent, and yes, it was basically crowd control and if they learnt something it was a result. There are some excellent teachers but unfortunately they cant do anything unless, a) the kids turn up in the first place the parents support the school when the school dare to "criticise" Little Johnny and c) the kids behave to an extent where learning is possible.
However, in my experience outside of teaching but within education the worst people to give the power to run schools to are Headteachers. When it comes to reaching targets and maintaining the image of the school the kids can **** them themselves for all a healthy proportion of kids care.
Should teachers be paid on results? Possibly, but looking at how may kids achieve x is pointless, the only way such a scheme COULD work would be for it to be based on a Value Added measure rather than basic results.
Until recently teaching has been a pretty cushy number, but changes to OfSted inspection regiemes have made it much much harder to coast along just getting by.