Here's the reason to get rid of it: If the other guy damages you bad enuf, and you die or have to bail some seconds after he is toast, or someone else kills you before he logs out, you do NOT get the kill. Alt-F4 is the guys last gasping pissonu move to rob you of the kill or get back at you for killing him. Sometimes it works. Further, if you don't realize he has logged, and you keep shooting at him, (and this works especially well in GV's) you waste ammo and likely get yourself killed by someone else. It needs to be disabled.
Spivey