Not sure if I agree fully with "U is responsible for ensuring ball not snapped prior to RFP."
Seems to me if C snapps it prior to RFP it's DOG. If A does not want DOG, C will not snap it.
I know, I know, they're only HS kids and it IS preventative for U to say "wait for whistle", but to say "U is responsible" for making sure A doesn't have their head in their rear seems to be a bit much.
Obviously when a wing goes under it opens up one side of the field with no coverage. nothing is prefect though.