Speed hack checking is vastly insufficient

Minecraft includes what amounts to a speed hack check by ensuring that players don't move too far in any one given move. Unfortunately this only checks the difference between the requested move and the previous move meaning that by simply spamming move packets with lots of small distances players are able to move much much faster than what would normally be allowed.

Unfortunately adding sophistication to inbuilt "hack" checks is fraught with false positives, but if some effort is going to be made it probably shouldn't be so trivial to bypass.

Addressing MC-80485 would also aid in fixing this issue.