I found one page saying that you absolutely positively must use 32 screws for one 4x8 sheet, although that was 16" OC.
Another page said that you absolutely positively must use 28.
It's official! Updated 01-29-09!
However, while trying to find anything newer, I found
this, which now accounts for 24" OC studs!
However, it doesn't account for edges, and despite clearly being a scan of a printout, it is newer, dated 12/11/18.
All right, I went through the website and found a fourth (one was from 2005) dated
3-15-22
Curious, linking documents only worked when I kept the punctuation in the URL converted into HTML codes.
What do you guys say, should I put four more screws in each edge?
Google Images mostly shows diagrams with equal spacing in the field and the edges, but those that show tighter spacing on the edges also show it on the floor.
Sure, it is an edge, but I am far less likely to notice imperfections, and I don't think that I will care, plus at some point I really need to figure out flooring (that can withstand sub-freezing temperatures!) and then I would be installing trim.