I agree with Robt.
I looked in my service manual last night and only saw two ajustments. One for the normal Idle speed and one for fast idel (associated with starting a cold engine).
I saw no other adjustments. If I recall there are others but they are WIRED SHUT for a dang good reason as RObt mentioned. Bench set up, controlled conditions etc. I'd claim against the folks who monkied around then get a real BIG bat and whomp they ass.
Eric