In FCP it’s Option + up/down arrow. I sometimes use this when I am nudging clips forward or back in the timeline (Option + left/right arrow… the hand & finger positions are already there). When I began thinking about the questions in my Original Post I was just going from many of my own FCP functions.
Anyway, I like how Premiere Pro moves clips around that contain transitions, it doesn’t see a “clip collision” like FCP does when you don’t have the entire clip + transitions selected.
On another note, I just remembered using whatever version of Premiere existed in 1996 for a college project.