Far from it. Why would I want to shoot at the range with a fouled barrel then hunt on a clean barrel? That makes about as much sense as sighting in with one bullet then when you go hunting to use a different bullet. You do what you think is best as I will.
Swabbing should have no difference in accuracy unless you constantly shoot/hunt with a fouled barrel. I want each shot to be as consistent as possible and that includes getting as much fouling out of the bore as possible for each shot.
Any propellant will leave some fouling in the bore and this fouling will alter the internal pressures which would change the POI from a clean vs a fouled barrel. To say BH209 doesn't leave fouling would be a downright falsehood. There is a significant amount of fouling left in the bore from BH209.
As for this topic being covered, yes it has and from what I can see on this forum and MML there are those that swab and those that don't. Yes the majority don't swab but there are a lot that do and for the same exact reason I stated.