That is indeed pure insanity. FWIW, I’ve seen lots of projects that way on Windows–it seemed to be common practice. And historically there was a good reason for it. For a very long time, include paths in the predecessors of Visual Studio were comma-delimited in a single text field, they were not recursive, and the text field was limited to 255 characters. (Yes, that was INCREDIBLY stupid, but it was what it was.)
