Has your co-developer ever been involved with development of the Bitcoin protocol?
Afaik, no. But I think he knows enough to do a reliable fork since he has forked Bitcoin before. But he wants to fork the latest version. I need him because I have not invested the effort to become knowledgeable about the Bitcoin source code. He may be asking me to help though on the Qt wallet modifications. I may also help on the op code changes we need.