>>539822254
I think you're ignoring the fact that there's a much simpler reason for focusing on a single character at a time. It's simply easier from a story telling perspective to flesh out one character when you don't have to work in the 3 other people sucking the air out of room. Sure, selling is a absolutely a part of it, but if you want to dump out world building and give a specific character some spotlight, it's easier to just sweep to board if any other distractions.