Why the netcode issue exists, and why it cannot be fixed.

[Kevee]

It can't be anything other than a simple check the server makes: Client tells server character is casting a spell so other clients can see the casting animation. Client updates server with location. .3 seconds later: client updates server with new location. Server sees location has changed and checks if previous casting action is allowed when moving. Sends notification that the client should interrupt casting if no. Doesn't do a thing if answer is yes.

Or maybe I'm misunderstanding what the confusion is with casting and moving?

Because if it was more of a client-side live-state, wouldn't the client cancel the cast on movement? I do agree with your other, bigger, post that the server is trusting your client(I have absolutely no credentials, it's just based off my my own personal anecdotal evidence), but the client should not allow that action in the first place.

This seems like a smaller issue(client allowing things it shouldn't) compared to the whole, and I don't want to detract from what is the problem.

What I want to say: I should not be able to move, use a spell/chocobo, and see a cast bar. Certainly not any part of it start to cast. I should not be able to move before a spell has finished casting, and still have the cast finish.
I should not have an interrupt-check be delayed. If I'm hit, by say Fireball from Twintania, it should interrupt my cast immediately. And all of these timings are never standard. They can vary wildly. Sometimes, as was said, you can complete a leeches/esuna cast completely on the move. Sometimes you can start moving as far as 1s left on cast.
I know that, generally, this has to do with latency, but it happens on far too regular of a scale, and especially compared to any other MMO.

Again, I don't have any credentials. I'm just your "average" person playing trying to give my input as to what I'm seeing, and what should/shouldn't be happening.


Edit: But if what your other post said was true, would that mean FFXIV has a client-side live-state while all other MMOs, generally, have a server-side live-state?