Great Consensus Cleanup Revival

A key aspect of this discourse is the proposal to set a cap on the number of BIP54 sigops to six for CHECKMULTISIG(VERIFY) operations, which stems from the recognition that scriptCode remains unchanged during signature checks in a single CHECKMULTISIG(VERIFY) operation. This allows for the potential caching of the six possible signature hashes, a method already implemented in Bitcoin Core version 30.0 as per pull request 32473. Despite its innovative approach, questions arise regarding its practical significance, especially given its primary impact on users involved with large legacy multisignature transactions.

The discussion further delves into the optimization of block space management by miners, particularly concerning the space allocated for coinbase transactions within a block. Bitcoin Core's default reservation of 8000 weight units for coinbase and header information is highlighted, with the possibility of reducing the minimum reserve to 2000 weight units or potentially even lower. The variability in approaches among different mining pools, such as Ocean Pool's usage of extra-large coinbases, illustrates the differing strategies employed to optimize space utilization within blocks. Additionally, the consideration of appending additional data to coinbase transactions to enhance efficiency introduces a nuanced debate about the balance between maximizing block space and ensuring transaction profitability.

Moreover, the proposal introduces technical suggestions for improving the handling of CHECKMULTISIG(VERIFY) operations by capping the number of sigops and exploring alternative nonce strategies for coinbase transactions. These include leveraging the nLockTime field as an extranonce and examining the implications of appending a 0 satoshi output with an OP_RETURN operation followed by a push instruction that adds a nonce. Such strategies aim to increase the hash rate potential and optimize mining operations without significantly impacting revenue.

The discussion encapsulates a broader narrative on the continuous efforts to refine and secure Bitcoin's transaction processing and mining mechanisms. By fostering open dialogue and collaboration within the community, these proposals seek to address existing vulnerabilities, enhance network efficiency, and lay the groundwork for future advancements in blockchain technology. The inclusion of test vectors and specific implementations for Bitcoin Inquisition underscores the commitment to rigorous testing and validation of proposed changes, ensuring that Bitcoin remains resilient against threats while adapting to evolving demands.