You are not gonna protect abstract ideas using copyright. Essentially, what he's proposing implies turning this "TGPL" in some sort of viral NDA, which is a different category of contract.
It's harder to convince someone that a content-focused license like the GPLv3 protects also abstract ideas, than creating a new form of contract/license that is designed specifically to protect abstract ideas (not just the content itself) from being spread in ways you don't want it to spread.