Great Consensus Cleanup Revival

This adjustment is based on the premise that within a CHECKMULTISIG(VERIFY) operation, the scriptCode remains constant, allowing for the potential caching of up to six possible signature hashes. This caching mechanism, as implemented in Bitcoin Core since version 30.0, reflects a sophisticated approach to optimizing transaction validation by minimizing redundant computations.

The suggestion raises several points for consideration, both technical and practical. On one hand, it acknowledges the efficiency gains from caching signature hashes and proposes a method to more accurately reflect these savings in sigop counting. This change could lead to a more precise budgeting of resources required for validating transactions involving large legacy multisig operations, which although less common today, still represent a valid use case within the network's broader transaction set.

On the other hand, the proposal also highlights potential challenges associated with implementing this change. The deviation from the current implementation of BIP16’s GetSigOpCount would necessitate modifications to existing codebases, introducing complexity not present in the current sigop accounting mechanism. This complexity arises not only from the need to adjust the count based on caching possibilities but also from the requirement to distinguish between different uses of CHECKMULTISIG(VERIFY) in legacy scripts.

Furthermore, the practical significance of this change is brought into question, given its primary relevance to users of large, legacy multisig transactions. The decreasing prevalence of such transactions could diminish the overall impact of the proposed adjustment on the network's transaction processing efficiency.

However, the gesture towards compiling a list of historical transactions potentially affected by this rule adaptation underlines an essential step in evaluating the proposal's merit. By examining specific instances where the current BIP54 rules might restrict transactions that would otherwise be viable under the suggested change, stakeholders can better assess the balance between increased accuracy in sigop budgeting and the added implementation complexity.

In conclusion, while the proposal to cap the BIP54-sigops in CHECKMULTISIG(VERIFY) at 6 presents an opportunity to refine Bitcoin's transaction validation metrics, it also poses questions regarding its necessity and practicality. The community's feedback on this matter will be crucial in determining the desirability of pursuing such a nuanced adjustment to Bitcoin's scripting rules.