I haven't heard that before, but I've worked with several programmers who normally write very readable code, and when they write a reduce or fold, it's like the

I haven't heard that before, but I've worked with several programmers who normally write very readable code, and when they write a reduce or fold, it's like they forget everything they know. They go super compressed and cryptic even if it's not their normal style. I can see why someone would want them to give it up.