30 minutes? Hm, I could do the whole Vault of Glass on normal in about the same time, that's if we have, as you say, decent players. Though, being as it is new, and not everyone has mastered it, I'm sure only the fastest could do that, my Brother has been attempting it for two days now and has yet to get to Crota. Could be that he's been in poor teams, but the difficulty is unknown to me.