Actually, if you were doing so well as to have enough to withdraw, why would you be in any rush to settle the account?
If you manage to turn your free $10 into $100, cashing out in the midst of so many easy pickings hardly makes sense, but at say $500, you would definitely want to know the path into your wallet is open.
In my eyes, it would be reasonable for any site to require a deposit before any withdrawal. So, you make the minimum deposit ($25?) and then pull out whatever works, maybe $300(?) of your $500 (or $525 after your deposit).
Actual confirmation would be nice, but seeing as I'm still working on that first $100, it's not really a concern for me yet....
(current EPL balance sitting at a deuce and a quarter )