Listen what percentage of players in this group even have the genetics to go pro? You can train 7 days a week it is irrelevant if you do not have the god given potential.
There may be 6 kids in the whole age group with this potential, now you have to find them. And these blind squirrels for coaches could find a nut in a chocolate factory!
Lastly you have to know how to develop them , let’s not even go there!