Using symbols like # before a quantity, @ before a unit price, or ⌀ before a diameter was considered critical for minimizing confusion. I think it was meant to work like a sort of Hungarian notation for numbers, so if someone’s transcribing them into an order form or something, and they find themselves copying a diameter into a price column, they catch themselves on the type mismatch.
It never seemed like there was much room for ambiguity in any of the lists I wrote up, but I guess when you screw up an order to a steel supplier and get the quantity mixed up with the length, that can be a pretty expensive mistake.
really though, with the "New Book called "What if? 2" by the XKCD creator, can I get him to sign it? given the previous books suggestion: a cure for the common cold, "If everyone on the planet stayed away from each other for a couple of weeks, wouldn't the common cold be wiped out?"? https://news.ycombinator.com/item?id=30139925
Was kinda amusing when the "less involved" classmates were trying to read it as B