Decrease at next diff. adjutment, not right away.
But there's no reason for miners to shut down right away. Mining at a loss might be worth it to drive the competition out of business. It's a Mexican standoff.
Clearly another moron. At current difficulty, a block would *never* be solved with just 2 miners. Blocks are solved in *about* ten minutes at current difficulty and current hashrate. Cut the hashrate, and the time to solve a block increases proportionally. Cut it enough, and you'll never get to the next difficulty adjustment.
I know right, some people think they know everything