Even though there is a special_remotes page, description there is quite superficial and does not provide a good overview of various aspects on special remotes

• life cycle, e.g. how they relate to Git remotes -- that they become listed among git remotes whenever enabled, that git remotes get the corresponding annex-uuid assigned when "sensed" or get annex-ignore, how to "disable" an enabled remote (just git remote remove)
• clearly list commands to operate on the special remotes (initremote, enableremote) or interrogate them (e.g. how to figure out if there is already a special remote with a target uuid but may be not enabled yet, etc)

Without such a documentation it is hard to "on board" new git-annex users and developers.

Hard to say that documentation is ever done, but I've made some improvements and I guess am going to call this done --Joey