Teaching how to write a link in Markdown is hard. It’s one example of the subtle horrors of horizontal complexity. Horror as in, the number of questions asked from intuition. Is it []() or ()[]? One question becomes two, with four answers, or more. Eventually ()[] = []() = ()() = [][]. But, is it [example.com][example] or [example][example.com]? The number of possibly erroneous actions among correct ones is a useful metric for automating (graphical) interfaces.