I've been using relative links in content in the past without any trouble. It has been suggested this is a bad practice, but the reasons given I haven't found terribly convincing. I may be wrong, but it seems as though people are using relative linking as a scapegoat for generally bad practices.
Take the following article for instance: http://yoast.com/relative-urls-issues/
The way I see it, if broken links are being deployed then testing isn't thorough enough. If a test environment is accessible to involved parties (e.g. spiders) then testing isn't controlled enough. If multiple paths exist to the same content without good reason, then the architecture is poor.
Looking around Google, this seems to be rather representative of the arguments. Relative links are bad because when they're combined with other issues that should never happen the results are undesirable. That's not good enough for me. Does anybody have a better reason?