Jeff... you have summarized it most excellently my friend! Far better than my (typical) wordy, verbose effort
And Marc... spot on, mate. While we do not want to excessively disturb the display water's surface if the overflow will feed a skimmer downstream of it, you would definitely benefit by disturbing the sump (better homogenizing of the matter) if a skimmer is fed by sump water.
In my presentations/lectures and sharing advice... I often preach of "finesse" as making great long term difference in husbandry. Attention to details such as these go a long way. Beyond a quality skimmer, the exact placement, water stability (or not), "thin-ness" of overflow water (concentration of proteins), and so much more make a great imp[act at times.
A funny aside... have you ever noticed that your skimmer performance falters just before and during a storm? The drop in barometric pressure influences bubble size (production). It makes the bubbles larger
