sounds like a very nice idea ,for specific duelists I mean (not including me)...more so, there is the YCM online game which is the same, almost, as KCVDS is...so in my view its a great suggestion.
Absolutely not. The potential for cheating is outrageously high and there is no way to control it. There won't be a time when DA allows you to receive DP for playing over Skype/MSN/AOL...etc.