I was in what amazon called double high density once. one guy had to duck under anoterh guys desk to get to his. so basically against fire code. the better way i've seen it there was where you will not quite bump into the person behind you if you push back. I was only in that once. usually I had an extra foot. I'm in low density right now it's good. Amazon never gave us smaller desks, they were always door desks. That would have gotten us more dense tho.

that's got nothing on what my animation co-workers dealt with in movies where they were just far enough not to bump elbows on the perimiter of a sound stage / mocap area. Worse they had a 2nd row of other coders above you on grating. They didn't let women on the upper deck due to look ups.