I would imagine if you're in a guild that never fills up then the chances of getting loot diminishes because of the size of the guild. By EQ1 standards, recruiting for upper guilds was definitely put on hold for a majority of classes at times. There was no point in adding a 6th warrior, because it would only thin out loot distribution and add no real significance to raids. Like you said it's all hypothetical though, based on whether there are contested mobs, instanced raid mobs, raid limit sizes, instance timers, ect. We have no idea what we will actually be getting here.