Yes, that’s what I meant by pushing the hump off the left side: it moves to the right.
Stars will clip with any exposure over about 3 s, so you’ll have clipping almost regardless of where you put the hump. Putting the hump just off the left side separates it from read noise and gives you the best dynamic range you can get with your sky noise level.
This doesn’t happen. Image signal can be fainter, stronger, or superimposed on the sky noise represented by the hump, and it will add linearly with time while the noise adds as the square root. The image will build faster with integration than the noise, and will “come up” out of the noise, regardless of where the hump is.
Check out the awesome images people are capturing from high Bortle skies. I’d call myself a novice, but this is my latest, with 18 hr integration time (and 60 s subs) from my Bortle 7 back yard. It just takes a long time to overcome all the skyfog noise, and extra processing to flatten out the wonky gradient which the light pollution produces.