I think part of the appeal of PrimeDice for many is that they don't require players to identify themselves. Changing that to "... unless you win too much" makes it less attractive I expect.
I said it in the context that such bets should be verified before allowing any withdrawals, even if players here are to maintain their anonymity, no worries at all, and I don't think players should have any problems getting their bets verified...
There's nothing to verify. Stunna knows his site is provably fair. The rolls will match the rolls given by the provably fair roll algorithm. The only problem is that the player knows his server seed. How can anyone ever verify that he doesn't know it?