Solving CoinPool high-interactivity issue with cut-through update of Taproot leaves

He provides a demo script that shows how pubkeys and balances can be committed, how data can be traversed and modified, and how signatures can be validated for exiting users. Johan mentions that the script can likely be optimized and explains that the size of the script and witness will grow as more users exit a pool. He suggests that this growth in size would not be an issue in most cooperative settings.Johan also proposes the idea of performing the exit process off-chain, allowing offline users to revert back to the original coinpool output when they come back online. He believes this could work as long as the committed balances and keys remain compatible. The only change needed would be updating the merkle inclusion proofs in the jointly signed transactions. Johan asks Antoine if this functionality aligns with what he was looking for.Antoine's email discusses the use of OP_EVICT in the context of an off-chain payment pool. He expresses concerns about the safety of using OP_EVICT and mentions TLUV or MERKLESUB as possible alternative solutions. Antoine notes that there is currently no sound covenant proposal that combines TLUV and EVICT-like semantics while still allowing for unilateral withdrawal of promised balances. He expresses his interest in finding a better direction to solve the high interactivity issue of channel factory and payment pool.ZmnSCPxj reaches out to Antoine to inquire about the suitability of using "OP_EVICT" for an unknown purpose. The email lacks contextual information but includes a link to a mailing list archive for further reference.The email discusses the issue of interactivity constraints in payment pools and channel factories. It highlights the importance of ensuring the security of user funds and the need for unanimous agreement on updates to off-chain balances. Various proposed solutions are mentioned, including the introduction of a coordinator, partitioning balances, or layering balances among off-chain user subsets. The email also discusses the challenge of mitigating equivocation of off-chain balances and suggests punishing cheating counterparties through an external fidelity bond.The author proposes a solution to prevent off-chain group equivocation by proactively editing the funding utxo of the pool or factory. This approach involves registering new off-chain subgroups as needed and includes the concept of "cut-through" spends to update multiple leaves with a single witness. The email provides an example scenario illustrating how this solution would work in practice. The author believes that such a solution could also reduce the chain space consumed during mass pool withdrawals.Overall, the emails cover various topics related to cryptocurrency systems, including the use of merkle roots, OP_EVICT, alternative solutions, and the interactivity issue in payment pools and channel factories.