lol, why do you think PB went client-side?
But anyways _every_ cheatprotection is at a loss when allowing clients that run on a selfmade OS .)
As long as a client has total control over what is sent to the server cheatprotection is laughable.
Besides that Trem has allready all that is needed to make it very hard for cheaters.
- Speedwalk? for a q3 engine? lol
- Wallhack? Certainly possible as it is already available and impossible to fight due to the way such a cheat can be hooked. But so what? it would only help humans in S1...
- Aimbot? Who wants to go to that extreme and do a complete recoding for movement prediction? Remember we only have one weapon that has insta-hit the rest is delayed. And an aimbot for alien? Come on, get real

Summing this up I really can't see neither a need nor a way to protect trem from cheats.