Four sheets on one ceiling sounds more like a guy problem than a method problem. Standing sheets up tears corners when you're forcing them into a spot that doesn't fit, that's not the wall's fault. Flat gets you cleaner cuts, standing saves your back on a 12 foot lid, pick your tradeoff and move on. A full house is mostly 8 foot walls anyway, so whoever swears standing wins is arguing over maybe 10 sheets out of 200. This is the kind of thing crews fight about while the board just sits there waiting.

Man, that Irish guy was speaking straight facts. I did the exact same thing my first long trip, holed up in a room in Chiang Mai grinding away and wondering why I felt so lonely and burned out at the same time. The move that worked for me was picking a cafe within walking distance of where I was staying and just becoming a regular, same table, same order, same time every morning. After like a week the staff starts nodding at you and random people start chatting because you're clearly not just a tourist passing through. My other trick is to do one non work thing every afternoon, even if it's just a walk to a park or grabbing lunch somewhere new, because that's usually where the actual trip happens. You nailed it though, the work gets done faster when you're not staring at the same four walls all day.