Tearing a tab into its own window makes it impossible to move. (I don't use tabs because they're too inflexible.) If I try to move a document, it snaps to a totally different spot. If I move it multiple times, it slowly migrates across the screen until it is impossible to work on at all. Turning off the tab setting altogether does not help this problem. In fact, at this rate, doing so would make getting anything done impossible.
Secondarily, it would also be nice if every new document window did not appear in my toolbar, because then I have to alt+tab through potentially 10 open documents each time I switch to Photoshop. Plus, it's really cluttered.