That was indeed my meaning. I'd read so many times about repeated resaving of jpgs degrading them, and I wanted to find out from my own experience how true it was, and how many times were needed to make a visible difference when viewed full screen on my monitor (again, note, not 100%). I probably used the jpg from a Minolta 7D for the tests, which fills the screen at 50%.
First, the mere fact that I can detect a difference after 6 saves implies that, even if I can't immediately see it, even one save will have lost something (jpg is a
lossy format, after all). And I don't see any need to lose anything if I don't have to.
As I work in black and white, jpg isn't a sensible file choice anyway; but I do work over and save tiffs several times. I don't rush setting up the camera and making the exposure, and I don't rush the afterwork. If Edward Weston could take 3 days to get a perfect print in a darkroom, I don't feel that I need prove my superiority by achieving the perfect print digitally in 5 minutes. More seriously, I find I need to have a "finished" print to examine at length and over a period of days becfore I'm satisifed that it is as good as I can get it.
I also use a Windows computer, and have for many years. That means I expect that (with early versions) it could crash at any time (which encouraged the habit of frequent saves). These days, on Win10, I know that at some point it will decide that for my own good it simply must reboot to ensure that essential updates are done, whether I want it or not (Microsoft always know best, after all). Hence, even if I intend to finish the editing, I can't guarantee that Microsoft will allow it.
Sorry - very off topic