This whole idea seems very nice for the very big WvW only guilds but for a guild that is PvX and loves to go around to all types of content such as raids, fractals, open world events, or wvw, this change sounds like a living hell. I dont know if there have been changes made since there are almost 50 pages of comments but it sounds to me if this goes through that player will be forced to play with 1 guild or another for WvW and be unable to play with their main guild that isnt very focused on wvw but still enjoyes it from time to time.IE my guild has been SBI for 6 years now and we of course there are those of us who wvw more than others and are in a separate guild for more intense wvw sessions, but we currently have the ability to play together without trying to get into an alliance who doesn't want us simply because we don't wvw as much as a whole will make trying to play with each other a nightmare.Ive heard nothing but excitement from my friends who ONLY wvw and ONLY play with their wvw guilds but it does not seem like the right path for the majority of the playerbase who likes to just occasionally dip into wvw with some friends when those friends are in guilds that require players to wvw a certain amount or alliances that will be against a guild joining that only a handful of players are heavily into wvw.
