Originally Posted by
seat38a
I can't find the article, but there was an article that I read written by a retired conductor, who explained some of the special marks they made on the seat checks as well. Depending on the position of the mark, it related to your race and gender. This was to prevent people from taking someone's seat check, and if someone did, the conductor could tell just by looking at it and then would ask for your ticket.
Wow, that seems like a lot of effort for a pretty rare case to catch. Sounds like far too much encoding for say, a short commuter rail journey.