Multisig Digital Bearer Instruments - peer to peer electronic cash

The email raises significant concerns and queries about the practicality and trustworthiness of protocols that involve transferring a private key and then deleting it. The key issue highlighted is the inherent uncertainty for the receiver regarding whether the sender has actually deleted the key, as there's a strong economic incentive to retain it. This skepticism extends towards the use of Trusted Execution Environments (TEEs) or Hardware Security Modules (HSMs), which, while capable of securing arbitrary computation, may not be ideal in peer-to-peer (P2P) settings due to practical and trust-related concerns. Questions are posed about the feasibility of demanding every participant to own such hardware and the reliability of such systems through attestation processes.

Further criticism is directed at the repetitive nature of the initial sections of a paper, which laboriously reiterate the deletion of Key A. This repetition detracts from the clarity and accessibility of the material, potentially obscuring more critical elements of the protocol discussed later on, such as the deletion of keys B and C, which are crucial to the actual transfer process. Additionally, the introduction of a third key in the context of an "Issuance" scenario is acknowledged, though its value addition is questioned, suggesting it might not significantly enhance the protocol's effectiveness or understanding.