@Anaximander: the important part is how does it look from the lagging persons perspective, not how it looks from the other ones. It is mainly about self control.
I do know how it looks from other persons perspectives as that one is usually explained by the victims. What is rarely objectivly explained is how it looks is likely to look from the persons perspective that is supposed to cheat.
For example:
I once, well over 2 years ago, had a pvp in Munich with 2 people on my side and 4 people on the other side inside the nebula to the north of the map.
I was fighting a guy that said he had developed a terrible lag while my ping and package loss was tolerable.
However the net effect was not jittering. The guy was sliding slowly in a straight line every now and then and was easily to be shot at. He did take all the damage that was done to him while he was sliding.
In other words, i do know that i was not lagging and no one else was at the time but him - and we all had a very easy time damaging him.
edit
first video : i cannot spot unusual stuff, but i only watched it once
second video : i see some erratic movements but freelancer always has poor accuracy when someone focusses on dodging alone
third video : yes, there is jittering
forth : same jittering and from what i read his ping was flawless? ( it looked like 56 or so with 0% loss )
To be honest, personally, i would not have suspected cheating in any of them had i met them, mainly because the snub dodging has always been too good for the weapons speeds and damage output