I think there's also an implied point that the key in a substantial codebase is more legally defensible than the key in a codebase that only provides the key.

I think there's also an implied point that the key in a substantial codebase is more legally defensible than the key in a codebase that only provides the key. In essence, the entirety of Dolphin's functionality provides legal cover for the small amount related to the key, under DMCA exception wording. Kudos to the Dolphin team.