Conversely only sysadmins think sysadmins can code. A classic example is a close personal friend of mine who works as an sysadmin for an insurance company.
On two occasions I've had the unfortunate displeasure of working with him on web-related projects (we share similar hobbies and our local communities need web services of various kinds) his approach has been vile, Rube Goldbergesque concretions of Perl & shell scripts.
This is absolutely THE GUY I'd call if I needed some advanced logfile parsing in a hurry, but when it comes to actually developing web stuff the guy's totally in the dark. What's worse is his only metric is "It works and it makes sense to me" so he's content to make a complete hash of a development project.
During a recent conversation he admitted to having no real grasp on basic HTML and hadn't heard of CSS. The thing that kills me is he's convinced he's qualified to run websites for our local groups and absolutely refuses to accept input on the subject.
Oh well, the guy's also an ace whitewater kayaker and one of my favorite paddling buddies. Considering this guy will probably save me from drowning one day I can look past his failings as a "developer".