[mattarm]

> Which is why unless is such a hard concept for people to grasp, not just in code, but also in regular English.

This is the first I've heard about this confusion over the word "unless" in English.

In spoken English I do notice that most often the "unless" comes after a statement. Example: "I'll be there on time, unless the bus is late." That is more clear (to me) than "I'll be there on time, if the bus is not late." Maybe not by coincidence, I tend to like "unless" when it follows the action in in Ruby code, too.