For what it’s worth, i think this could be of use as a sibling proposal to Tadge’s OP_CIV, as a poor-man’s signature aggregation scheme for post quantum signatures.
Though, unlike OP_CIV or my proposed alternative, OP_CC requires committing publicly to the exact same address for it to be used when spending. I think if you were gonna go this route, you’d want to at least offer users privacy until spending time, when they select which UTXOs to associate by the common-owner-input heuristic.