It's a clever idea to DDOS the major pools in order to decrease difficulty. However, is that sustainable? A DDOS would have to continue for a day or more in order to impact difficulty, I'm guessing. Can anyone provide some math to show how difficulty would be impacted by 50% of the miners were offline for 1 hour, 12 hours, 24 hours, 48 hours, etc?
That should not be a problem. Often, botnets are used to facilitate DDoS attacks. Since the infected computers are most likely spread all around the world, there will always be enough of them online to continue the attack.
After difficulty decreases, watch to see which major new miner or pool comes online. Perhaps they were responsible.
Well, that would be too obvious. I don't think anyone would be this stupid, but I have underestimated people's stupidity before...
I always thought an easier way to manipulate difficulty would be: Legitimately take yourself offline, let difficulty decrease, then come back online to generate more coins at lower difficulty. When difficulty raises, take yourself offline again. An entire mining pool could do this. Again, math would be needed to reveal the profitability of such a move. Mining time lost while offline during high difficulty could be made up by increased profits while online during low difficulty?
But why would you take yourself offline? Even if the increased profits during low-difficulty phases would make up for the profits lost while being offline, it would be more profitable to take out another pool. If another pool goes down, you still benefit from decreased difficulty, but you do not have to stop mining.
And since you can buy access to botnets, there just has to be somebody who is convinced that the additional bitcoins he creates will be worth more than the dollars he paid for the botnet. Or maybe he even paid for the botnet in bitcoins...
Anyway, I will check on deepbit tomorrow. Had my laptop mining for them and was less than 0.011 bitcoins away from payout