This centralization is feared mainly because of the potential legal and political pressures that could influence which transactions are selected for inclusion in blocks. The notion that pool hopping could ensure decentralization is challenged by the reality that if there are only a few pools available or if they all use a similar set of transactions for their blocks, the desired effect of decentralization would not be achieved. Moreover, the variance reduction, a benefit of having many pools, might also contribute negatively to this issue.

The email outlines the inherent difficulties in making Bitcoin censorship-resistant under the current mechanism of transaction selection. Every region has entities that it wishes to exclude from the network (e.g., political rivals, criminals), which complicates the goal of maintaining an open financial system. One proposed solution to combat these challenges is the adoption of a deterministic algorithm for transaction selection, which would require consensus on the mempool's contents. This approach necessitates a committed mempool with consensus across participants, something that could potentially be achieved through decentralized mining pools like P2Pool or Braidpool. These pools could add metadata blocks containing transaction data to their weak blocks, ensuring no conflicts between transactions and creating a large, consistent block without size limits.

Implementing a deterministic block template algorithm offers several benefits, including eliminating the need for communicating block templates to sharechain nodes, thereby speeding up validation processes and reducing communication bandwidth requirements. However, this method does not entirely solve the problem of transaction censorship but shifts it to the share chain level. Transactions must first be mined in the share chain before being included in the main chain, presenting a new layer where censorship could occur. In the case of a double spend or conflicting transactions, the system (whether based on P2Pool or DAG models like Braidpool) would resolve these through mechanisms that prioritize the highest work-weighted path, though efforts can still be made to change this path and affect transaction inclusion.

Overall, the email presents a critical view of the current transaction selection process in Bitcoin, proposing a shift towards a more deterministic and consensus-based approach as a means to enhance decentralization and resist censorship. This proposition involves complex technical adjustments and a rethinking of how transactions are pooled and validated, aiming to preserve the foundational principles of Bitcoin while navigating the practical challenges of its operation and governance.