Instead of sharding the zones, their plan is to shard the entire continent at launch. In Classic WoW, there are no dynamic spawns and questing in starting zones would quickly become annoying, so it's understandable that the game is all but fun when there are no mobs to kill, but layering will also cause you to see new players, every time you sign in to the game, which is a clear downside of the tech.
HOWEVER, I did find out that there was an exploit to get around it (one of those rare exploits where you would WANT a bit of lag). Basically if you spammed “X” to sit/stand/sit/stand, then if a mob hit you while you were sitting and right as you were standing up, then it would register as a crit, but on the server side you would be standing, thus allowing the ability to proc.
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