Spreadsheets with View permissions for one group of keys and Edit permissions for another group of keys is frying my brain at the moment.

The good part is that once this is done, any replaceable event in nostr can have these collaborative features and can go back and forth between all these modes: single-user private, single-user to private group, multi-editor to multi-viewer, to fully public.

All with just a few changes to the tags. No need for NIP46 or any shared signer setup.