Yes, it mentions this in the instructions. Just wanted to confirm it doesn't have some sort of outlying affect.
On that note, low spark operates the same way (only at low load). I'm curious to know under what conditions you would use this adjustment and what effect it would have by adjusting up or down?
On the low load spark, it would be rare to need to adjust that, but some people like to experiment. It may affect gas mileage, or throttle response, or if there is light load knock.