>One's person expensive computation is another person's almost free computation We have pretty good guides to what's an expensive computation to everyone. That

>One's person expensive computation is another person's almost free computation We have pretty good guides to what's an expensive computation to everyone. That's how password-hashing algorithms work, much better than BitCoin does. Besides, the existence of specialized methods of compute is hardly determinative. We're not trying to stop TLAs. It just needs to be expensive enough to stop 99%, and at most we'll later update again.