I think Rugby is even worse due to greater amount of physical contact - although on the flipside it is perhaps better preparation for the 'real world' i.e. physique can be limiting even in the adult game.
I had some crazy ill-conceived idea about how children's football should be based on height bandings rather than age, which would mean you wouldn't get a situation where some teams have a Peter Crouch to punt the ball up to, and equally Peter Crouch would actually have had to learn how to jump for headers rather than simply stooping his head (watching him over the years I'm convinced this is why his technique in the air is so poor, in schoolboy football he probably towered over his peers and so never properly developed or learnt how to time his jumps). Of course there are a lot of reasons why it wouldn't work and would perhaps penalise taller players (i.e. a 12 year old thrown in with 15 year olds with 3 years more training and under their belts plus a stronger build). Plus Messi in the U14s, lol.
