[Pierre-Marie Baty]

Short answer: this is impossible. The ping of bots is hardcoded in the HL engine, and there's nothing we can do about it.

Long answer: if a cracker could narrow down the byte in memory where this ping is stored, the bot coder could eventually try to "patch" it. But it would probably be VERY unsafe, plus any Steam update would break it and we would need to redo it all over again, and furthermore doing this requires a lot of time and skill which could be spent elsewhere.