What should turning ELR adjustment "feel" like?

[Shortsguy1]

Okay, perhaps a stupid question, but my w124 idles fine, but I am always trying to learn more about the car. So I adjusted the ELR adjuster (sorry if it has a better name) by pulling it out and turning. It was able to be turned in either direction without any stops. In other words, it could just spin and spin in either direction. And it didn't do anything to the idle of the car.

So I know it has 7 or 8 settings, but as you turn it, does it stop at each setting or is it a continuously smooth adjuster? Can it be turned more than 360 degrees? To get a change in the idle, do you have to re-engage the knob to its normal position, or should the idle change as you are adjusting it without necessarily re-engaging it into its locked position?

Someday I want to get this system working again and I know it has several parts. But I thought I would start with the adjuster, because its behavior just didn't seem normal to me. Thanks for your time.