If you're still getting the kills why does it irritate you?That issue is annoying. It's my greatest issue with the default control scheme. I'm hoping the custom button mapping can fix this.
Also, don't forget that toggled crouch is default. Some people may not be aware of this and have not changed their settings. So now when they get into a firefight and clench, they stay crouched. Also, I think some people may brefer to leave crouch toggled due to less crouch jumping and having the ability to slide into cover.
Embrace the clench.
I used to be quite the try-hard back in H2 and later H3. A buddy of mine that was some sort of savant at Halo gave me some good advice: Stay completely relaxed when engaging an opponent; do not tense up.
He was absolutely right, too. Once I learned to stay calm my game got a lot better.
Clench-crouching means you are panicking. Get that under control and you'll see a lot of improvement.
I wish I had the time to be a complete try-hard like I once was.