I completely agree with the general assessment, but then there are always pesky exceptions. In this case the list entered a JavaScript frontend from the yaml header of machine generated content pages for the website framework Hugo. And, of course, after finding the bug, it is clear that things could have been done differently and the issue easily avoided, but I also don't think this was a completely unreasonable design. Since Hugo actually supports JSON headers (not just via the yaml parser, but thanks for that tip!), that was a quick fix. But I'm also somewhat amazed that it was possible for the strung-together fairly standard set of Python libraries (primarily pyyaml) to not get the strings properly quoted.