I've cleaned 1000's of primer pockets one at a time because I thought I should. Now they are cleaned coincidentally with tumbling--when I tumble. I learned long ago that after a handgun shooting session, I could dump the empties onto a big towel saturated with lighter fluid and then roll around for a light clean. A batch thus treated would reload nicely and shoot just as well as the super clean ones. I not saying that those new to hand loading should forego the brass cleaning step but am stressing that super shiny brass, though nice, is not essential. Just regular old clean is very good. Brass gets clean way before it becomes shiny.