lvl 9 FH with 670 att + is not "average" player. It would be disastrous, and this guy never said he had 200k pults to bomb on the 12

as for troop count, I'd wait for 1-1.2M archers, because there's no point in taking a 12 if you cannot defend it. As for the actual takedown, there are plenty of guides, with screen shots about how to do this.