Unless the mechanics/mob count changed a fair amount, it would just mean taking however many extra DPS while still only rolling with 1-2 tanks and healers. Reminds me of Dynamis back in the day. 30+ person raid but you typically only carried 2 tanks and there'd be 1 healer for each party in the ally except the tank pt which had 2. You would have FCs that ran their two top tanks and any other tank main would be SoL or have to run on an alt class and never be able to Need gear.