Did not someone mention a methd of digging the holes, placing the
posts, bracing them, filling the holes around the posts with dry
concrete mix then watering the mix. Whereupon the cement sets/cures in
place? I vaguely recall some postings along that line (on this NG?).

That's how I always set mine, it works great. If you get it a little
too wet, no problem, the excess soaks into the dirt. I just use a 1X2
to stir / mix. Why get something messy mixing cement for posts?