> Sacrificial PoW (as in LF, hashcash) only has value if reorgs happen. That's assuming you need a reorg to adjust values. The original purpose of hashcash was

> Sacrificial PoW (as in LF, hashcash) only has value if reorgs happen. That's assuming you need a reorg to adjust values. The original purpose of hashcash was anti-spam. That lends itself to allowing variable work factors and having the recipient's classifier regard higher work factors as a stronger not-spam signal, with the baseline set by the recipient administrator, or the mail daemon packager setting defaults for this year's distribution, as a trade off between false positives and false negatives. Meanwhile a sender default of e.g. calculating hashes for ten seconds per message would cause the amount of calculation done to automatically rise over time as people buy faster hardware, but someone with slower hardware can reduce the false positive rate for their messages by increasing the time spent per message. Or someone with a high message volume but widely known and sterling sender reputation could reduce computation per message and rely on their good reputation instead, while less well known senders avoid spam classifications by doing more computation. It works because it's all probabilistic anyway and having non-zero false positives or false negatives was already the status quo, so something that gets you closer to true is valuable even if it only solves 99% of the problem and not 100%.