It has tons of drawbacks
Yeah, i'de say a lot more drawbacks then the traditional way of thinking would result: how to synch gameplay.
Knowing that the system works like this (which everyone would, very quickly), it would lose interest extremely quick.
This is something that was 'emulated' for me, by a snes 'emulator', using udp packets instead of tcp, where on my screen I would beat the person I was playing via netplay, and they would think they were beating me, until 10 minutes later we realise we arent even in the same game as we completely lost synch long ago.
More pissed off then impressed, and I can't see a better reaction then that to such a system.