That's great if that works for you. But for me being productive often includes multiple PDF files or editor windows being open and having them all float or just two next to each other just isn't an option. With a tiling wm I can have 4 or 6 windows PDFs open on a single 24" monitor and that works perfectly.

Just let people decide for themselves how to be productive, it's great your work allows you to be productive on two windows, some other people may need more, some less.