They should disable jumping in PvP altogether as it is not needed at all and just leads to problems like this. Every decent melee player is just spam jumping and cheesing the connection, but I've only seen ONE instance where I believe the guy was actually speed hacking (he was heavied, I was sprinting, he outran me). It's just very stupid.
However, I think that the game doesn't re-ping your position until you land..which is why I believe this monk got hit by this Terminal Velocity to lose the game haha.
https://youtu.be/qw1F0gTgp2Y?t=8m40s
If you watch the whole game, notice the Monk moving as I stay on him for most of the game, and then how it is when I'm on top of the Warrior. No crazy snapping a few feet or anything like that. I know Fer Li is a good player, and I don't think he is speed hacking but the jump spam really is stupid.