First off, a disclaimer: This post is intended for ZOS and their network engineers. Those who don't know what "replication" or "remote client" means should probably just observe. I won't really be replying to anyone who doesn't demonstrate enough knowledge of networking games to discuss this properly.
Animation cancelling exists and ZOS refuses to remove or fix it - FINE.
However, it is completely and utterly broken for remote clients, because the minimum possible animation delays *with* anim-cancelling are NOT being replicated properly, resulting in multiple skills landing instantly on remote players, despite the local player seeing those delays on their own client.
Needless to say this is incredibly broken and allows macro users to cheat in an extremely broken way.
The minimum time between skills *must* be replicated across the network properly, and it is not currently at all.