What I have read and also experienced is that producing quantity is necessary but not sufficient for producing quality. If you want to get really good at something, rather than just getting somewhat good and then plateauing, you have to not only do it a lot, but you have to care deeply about how good you are doing, identify your weaknesses and work specifically to improve those. The problem with your story is that the quantity kids have no incentive to produce quality, so they probably just won't.

A different angle from Kenny Werner, though this is about music-- his Effortless Mastery is about learning to be calm and non-judgmental, then gradually adding more challenge (achieve state, approach instrument, touch instrument, pick up instrument, make sound without aiming for good sound, then slowly add work on getting skillful without disrupting meditative state).

I haven't seen this approach applied to purely cognitive work like programming, though this doesn't seem impossible.