66 on sv_minupdaterate and sv_mincmdrate is too high! around 40 would be OK.
The Client cant send more Updates (mincmdrate) than his amount of FPS.
My Computer cant hold 66 FPS stable on a zm server with 50 and more players. My averange FPS is 35 - 40. And i bet im not the only one. So the server gets only 35 - 40 Updates from me, even if its forced to 66.
A Player is harder to hit when the Clients effective cmdrate deviates too much from the forced updaterate of the server.
And the EH Server cant send always 66 updates (minupdaterate). It often goes down to ~50, sometimes even to ~30.
Servers with that many players and many plugins are too huge to force high rates on it.
And i guess the long knife problem is caused by the lag compensation, not by low-raters. Its the same story like "I was already behind the wall, but he still hit me!".