I don't use the 2 bucket method either. I rinse off my mitt after each panel. I think the 2 bucket theory is the same thinking as the bath to shower argument. Not trying to argue with anyone, just pointing out my thinking into this. If you rinse in a ashower the dirt/grime is off and down the drain. If you bathe, then some of the particles can go to the bottom and depending on how fast you get up from the water you can grab a bunch of the particles you were trying to wash off. So rinsing after each panel, while wasting a lil more soap, will kepp you from having more chances of scratching/marring of your surfaces.
Just my $0.02
Jim
Just my $0.02
Jim