>If the drop is smooth it would not be a problem. There can be a problem if there is a very abrupt drop and until the next difficulty recalculation the block ge

>If the drop is smooth it would not be a problem. There can be a problem if there is a very abrupt drop and until the next difficulty recalculation the block generation rate would be too slow. That's always been a weakness in the difficulty recalculation algorithm. There are a few other ones out there that can do much faster re-targeting in interesting ways, such as gravity well[1]. I'm assuming that if we faced a sudden exodus of that scale that dramatically wedged block generation, we'd see a hard-fork to change the recalculation algorithm. The hard-fork would certainly win because anyone who refuses the hard-fork can't mine blocks due to the difficulty being too high for the network. [1] https://bitcoin.stackexchange.com/questions/21730/how-does-the-kimoto-gravity-well-regulate-difficulty https://bitcoin.stackexchange.com/questions/21730/how-does-t...