if you have been playing left 4 dead for more than a few hours, you no doubt have come to the realization that crouching is a very important strategy. when a zombie horde hones in on you, it’s a good idea to huddle up with your team mates in a corner. you and another survivor can crouch in front and shove the zombies back, and two people behind can fire over your head to disperse the zombies more rapidly. why then are you required to hold down the crouch button for possibly dozens of seconds to remain in this strategic position? i don’t know about you, but my finger gets tired holding that button down.
fortunately, my friends, there is an easier way. if you hunt down your autoexec.cfg file that i told you about previously, you can add a command to the file to change the crouch behavior. the toggle_duck command will reverse whatever state of crouch you happen to be in; if you are currently standing up, you will crouch when pressing the button. if you are crouched, pressing the button will make you stand up. sweetness, right?
i use mouse button 4 for crouch toggling, but make sure you insert whatever key or button you use in the following command:
bind "mouse4" "toggle_duck"
now you just press or click once to crouch, and again to stop crouching.
i find this very helpful for the hunter as well, because you can be ready to pounce at any time without fear of standing up when in the heat of battle!