Escapist have an article about the activities of Fansy, on an Everquest PVP server. It’s interesting in a couple of ways. Their point about the unchanging nature of MMOs is easily the most disappointing aspects of MMOs. Old school MUDs had much more scope for change, at least once you got to a high enough level.
The first system that successfully provides for a fungible environment will be vastly successful. It’s difficult though. They need to cope both with the griefers, who will actively try to ruin the environment, and with the “fixed point attractors” in their rules - sort of heat death for MMOs. My instinct is that almost all rulesets will result quickly in point or cyclical attractors.
The second point from the article is of course that Fansy was a griefer. He is lauded in that article, but he was exploiting server rules to ruin the game for others. As such, he probably ought to have been terminated immediately - it was only the conceit of a “rules free” server that stopped them. Of course it wasn’t “rules free” at all - if it had been, Fansy would have been dealt with immediately by it’s inhabitants.
The final point is how MMOs really dealt with the Fansy problem. They rewrote mob engagement to rubber band at a distance from the mobs patrol zone, and they tweaked threat so that the originally aggroing player maintains threat.
Problem solved - no further risk from training (unless the victims actively participate by generating threat). The article wants to make a point about how restrictive rules are, so they don’t mention it, but it is in fact the essence of MMOs (and the real world too). Tuning the rules in microcosm can have huge effects on the overall playability of the game. Just look at the effect of poorly designed sub-prime lending rules on the global interbank trading market if you don’t believe me 
So I didn’t understand a word of that (apart from the last sentence!)
That’s silly, bad guy teams were just as much ‘griefers’ as Fansy was. Camping the corpses of players in ‘good’ zones who had barely hit level 7– the first pvp enabled level– and so on and so forth. No, that is not breaking the rules per se, but neither was the ‘training’ that Fansy was doing. You say that the inhabitants themselves would have been able to police Fansy if there were ‘no rules’ but the same applies to a character 30 levels higher than you sitting on your rotting corpse with 100pp worth of items. Good luck finding another level 50 on the ‘good’ team to help you out, when it’s 10% of you vs 90%. You neglect to mention how MMOs have dealt with not only trains but the issue of corpse camping in PVP, which to me, was much much worse than a training monsters. Theres always a chance to survive a train. There isn’t a chance to survive a corpse camper who is watching a dvd on the side with infravision on, just waiting for you to come back, hour after our. Damn straight Fansy was lauded.