WebDAV is kinda bad, and back then it was a big deal that corporate proxies wouldn't forward custom HTTP methods. You could barely trust PUT to work, let alone PROPFIND.
When I was in school, we had a SkunkDAV setup that department secretaries were supposed to use to update websites... supporting that was no fun at all. I'm not sure why it was so painful (was 25 years ago) but it left a bad taste in my mouth.