Exactly! Being able to reliably read 13 cards a second from a stack is quite a feat, requiring precision components such as picker knives and jogglers moving at

Exactly! Being able to reliably read 13 cards a second from a stack is quite a feat, requiring precision components such as picker knives and jogglers moving at high speeds. (I am not making up the joggler; it uh joggles cards into alignment.) Optical reading would avoid the metal brushes, which get out of alignment or make intermittent contact, but that's not the hard part. Yesterday's "Why Paper Jams Persist" in the New Yorker is also relevant, a look at why its difficult to move paper through a printer reliably. Punch cards, being made of paper, have the same problems but worse - they are weakened by the holes, and mistreated by the public. (Older readers may recall "Do not fold, spindle or mutilate" printed on punch card utility bills and such.) https://www.newyorker.com/magazine/2018/02/12/why-paper-jams-persist https://www.newyorker.com/magazine/2018/02/12/why-paper-jams...