Re: Kevs' comment about prints abrading each other - I have never had this problem, or the unequal toning problem either, for that matter. Maybe because when I do this, up to say, 10 - 15 prints at a time, I am sure to use a tray slightly larger than the prints, with at least an inch of toner. I also shuffle them bottom to top, like film open tray developing. The depth of the toner solution and the rotating keeps the prints from settling or sticking to each other, which could be the cause of these two problems. Maybe I've just been lucky.
I do this because many of my images are 2 or 3 image pans, and I want all of the prints to have the same toning. I also make 3 or 4 sets of prints and tone them in one batch, just to be sure I have at least two or three matching sets for framing.