I did that job for a little while - they warned me before I started that once you learn to see cue marks (little black dots in the upper right) you'll never not be able to see them.
And they were right. But it was lots of fun yelling out "cue" during random TV shows, or with platter projectors, when there really shouldn't even be a cue mark :)
The cigar burns were useful when we would still reel switch at Campus Cinema in the early 2000s on second run movies. We could fit only 3 reels on a medium reel, no platter. Got that job because I worked for Edwards Cinemas on 35 and IMAX. It was fun, but I watched it die as an industry and a trade sadly. Got to listen to lots of memories of the old timers.
Jim Edwards used to show up at one of my local theaters in a sort of usher suit and I loved asking him questions. He was old-school taciturn. They actually had good, fresh popcorn and many very good theaters before they were acquired.
Similar to that, I used to find it hard to watch a movie in a different cinema where the projectionist didn't pay too much attention to detail when framing.
Sure most of the picture was on screen but for like 30second more attention it could be great on screen
And they were right. But it was lots of fun yelling out "cue" during random TV shows, or with platter projectors, when there really shouldn't even be a cue mark :)