I had been working with a mental model based on what I read a long time ago here (Rusty’s gossip v2 proposal, I think the original one? Hard to keep track).
To crib from there:
- Nodes send out weekly node_announcement_v2, proving they own some UTXOs.
- This entitles them to broadcast channels, using channel_update_v2; a channel_update_v2 from both peers means the channel exists.
- This uses UTXOs for anti-spam, but doesn’t tie them to channels directly.
- Future ZKP proofs are could be added.
He also has a concept of claiming the channel on open at the end of that post. Obviously in that model, my perspective should make a lot more sense.
But it seems pretty clear you’re looking at it differently (as per the OP, v1.75 but with zkp added in). Responding more directly to your Q, though, I think you could make this argument: single funder provides zkp, dual funders have the starting channel balance reflect the asymmetric cost of one funder making a single proof; but as you can see this is fudgy, and maybe I’m wrong. I personally find Rusty’s model makes a lot more logical sense, taking anti-DOS as far away as possible from the blockchain and making capacity claims vague).