I have lived at both ends of this discussion.

Last summer printing at a pal's cabin. Power from solar cells and batteries and an invertor. The electronic timer hated the harmonics from the invertor, and the mechanical one very cranky also. The solution was to stop the lens down, and steal the metronome from the next room. Base exposure count 9, start dodge, coutn 12 cover lens. Set up for burning in, light on, count 3, cover lens, light off.

About 20 years ago, print the grad photos for the faculty of engineering at my uni. over 160 portraits, all shot by me under the same light, same film, same development. Dial in the contrast on the first one at 8x10, crank the head down for the small print sizes required, open the lens up to f/8 and let the auto repeating time do it's thing. Exposure time was 3.1 seconds, and repeated as fast as I could shift the negative to the next frame selected for exposure, and swap in a fresh piece of paper.
The 36 exposure 35mm film was not cut and sleeved until after all of the prints were made, to make it faster to move on to the next needed neg.