For the moment it is only a proposal.
Since the Cite extension is used at most wikimedia wikis, it has to be discussed with the developers. This is why I posted the original message to wikitech-l ; wikisource-l was only in cc.
I realize now that it was not a good idea to send the same message to wikisource-l, because users of this ML do not know that there is a discussion at wikitech-l
Thomas