This would actually be a fantastic time to consolidate a list of all attributes into one location. Would you be OK with compiling a list of all attributes and just warning if it's not in there? The logic could be to warn about obsolete attributes (with a nice message), and then checking to see if the attribute is listed in any of the known attributes.

We may not necessarily be documenting all the attributes in one spot, but it'd be awesome to have them all listed (and it'd be annoying if you didn't add them to the list).