The non-outsourceable puzzle discourages hosted mining as well as pools (though if users are trusting, then hosted mining might persist anyway). The non-outsou

The non-outsourceable puzzle discourages hosted mining as well as pools (though if users are trusting, then hosted mining might persist anyway). The non-outsourceable puzzle would have to be adopted at the same time as another change, which would allow solo-miners to enjoy the low variance they get in a pool. Essentially you would need to allow miners to choose a lower difficulty, for proportionally lower block reward. This opens up DoS concerns if it can go arbitrarily low, and might generally require more bandwidth. This would essentially be Bitcoin internalizing p2pool.