What is SGP monitoring to "Settle at < x.x pixels"?

It doesn't make sense that settling was happening with dither off. AFAIK
there's no way to turn off settling, but you could try going with the max
error 2.5 with a settle time of 0 sec. I think that means that any time
the error gets at 2.5px or below, even for an instant, the sequence should
resume. But again, I too would have thought that if dithering is disabled
there wouldn't be a settle time at all.