Yes. I was thinking of something similar myself, except that the original poster of the article, Alice, has what is like the "canonical" version, and changes are proposed and merged into it, unless rejected by Alice. If Alice merges them, no need for Bob to agree or have his own version or maintain it. Perhaps an edit history can show what changes Bob made to Alice's article.

If Alice rejects Bob's edits, then there would be a separate "Bob version" of the article which he is now the original author of and maintainer, alongside Alice's version.

Kinda like what you wrote, minus the fourth step. What do you think?