A look at SHRINCS

The recent discussion about storing key usage data directly on the blockchain has raised several practical considerations. The simplest approach to track the number of times an address has been used involves scanning the entire blockchain and all transactions. This method, however, is not feasible for pruned nodes which do not store the full history of the blockchain. An alternative for these nodes could be to obtain this count from a non-pruning node or by resyncing their node from the genesis block, although these methods require significant resources and can be optimized.

A potential enhancement suggested involves appending the usage count directly to each transaction sent from an address. This approach would allow any user to easily check the most recent transaction to determine how many times a specific address has been utilized, simplifying the retrieval process significantly. However, this system carries limitations, particularly concerning off-chain activities. For example, it wouldn't track off-chain signatures, such as those used to prove coin ownership in applications like ticketing systems, nor would it be effective for addresses used within the Lightning Network. Alternate tracking methods must be developed for these use cases to ensure comprehensive monitoring of address utilization across different platforms and technologies.