It's probably that the first people who printed them averaged. It's what machines do without a human leading them.
It sounds like the second operator knew, partially perhaps you pointed out the problems, that he needed to manually print the shots.
"Developing" would usually involve the latent images on the film, although of course prints must be developed, too. Thing is, the problem in printing is usually the exposure, not the development, well, unless you're one of a few places I've had the misfortune to visit, once each.
-- Do not seek the treasure! DO NOT SEEK THE TREASURE!
