I never liked knife TDM's.
I have played it, but i sucked at it and didn't think it was much fun.
I think i played a grapple knife TDM too.
And i thought it was handicapped.
Why do you give the players a tool to avoid dying of a mechanic that made it challenging?
Anyhow, still don't like it and i avoid the servers.
My brother plays on them sometimes and i watched him play it a bit.
He got owned so many times, but yet he likes it.
There is this one with a level system and from what i heard it is like this:
The higher your level, the further you can knife people from.
If this is actually true, then that is really forgeted up.
Tl;Dr I don't like any version of Knife TDM, i suck at them too (not the main reason why i don't like them, but it helps), and the grapple knife TDM is handicapped because you give players the tools to avoid a mechanic that was posing a challenge.