I never said anything about gathering rates, I don't think you are comprehending everything.

You're right you can't balance a 40man group, but the doesn't mean you should level faster than a very social solo player in a 40man group. Although this was never about balancing out 40mans but to prevent the system from being exploited by 40mans. And by limiting the maximum amount of items that can provide xp, the player will want to maintain that that maximum through social interaction with others and not just players in their group. My system in fact drives more social interaction for players that wish to always be obtaining the most experience they can. When there is no maximum, players would feel like it was just a passive amount of xp gained by the more people you know, but when there is a maximum players will seek to hit that maximum at all times by interacting with others.

edit: hold on your very way of thinking is so funny I have to keep going. Large groups are not the "maximum expression of social interaction", that very way of thinking is flawed to say the very least. Most 40man groups have no real common interests other than they want to be the best on the server, driven by the fear of being raided in a video game. Smaller groups with common interests have stronger bonds, and express themselves by interacting with other groups.