Well, the original idea was that major gangs would create one unarmed or melee char and they would fight 1x1 somewhere (New Reno, does not matter) to settle down their disputes. No need to implement anything. Players would come, look at fight, after end players would go away. During fight, players would not attack each other (except those 2 unarmed fighthers, of course). Its kind of chivalry tradition. Even enemy, after 2 years of playing on same server, we could behave like a men, not child. At this moment, acticity on 2238 is minimal, because everybody expects wipe, there are a lot of different fonline servers, .. . So i hope this tradition would start at least after wipe on 2238. Again, nothing is needed to be implemented. It depends on players and gangs.
Even gangs are in same alliance, they can manfight in thunderdome among each other. Thats all.