Not sure why the rule would need to be tested? The rule does not allow anyone to factor in contribution toward football development (whether or not that is correct is a different debate - I would argue it should be a major factor).
They are just kids - why anyone would pay $5k for a junior footballer is beyond me.
I recall one player who transferred from Centrals to Port as a 14 or 15 year old and by age 18 he was playing lawn bowls instead of footy. May as well drop the $5k into the pokies back in the club room.
Some stats on ROI for transferred junior footballers would be interesting, I reckon they would show that it just isn't worth bothering with.