that'd be a game of diminishing returns, though. You'd need to have 100% of net hash to secure that the fees are coming back to yourself. And even if some portion, mining has its associated costs (unless botnet). True, the ongoing bitcoin DDoS attacks also have a cost associated with them.

Ultimately, the DDoS against the monero blockchain wouldn't interrupt service or drive the fee up. All it would do is bloat the chain. Hrm.... though it might be possible that a DDoS would work though due to megablock network propagation. E.g., if said attacker had enough monero to ramp the blocksize up to 200 MB, each relay of the block would take 73 seconds (at 3 MB/s, http://techinternets.com/copy_calc?do). Sure, 200 MB is a ridiculous blocksize, and I have no idea how much it would cost to ramp it up to that size... from what I remember of the blocksize algorithm it can take a while.

though it is interesting.... in light of the fact that larger blocks take longer to propagate, miners theoretically have an incentive to publish blocks that are within the transmission capacity of the network. E.g., if the current blocksize is X and I can make a new block with 1.25X (or whatever the max allowed in the protocol is)..

actually, is there a minimum blocksize?   I.e., for the algorithm, is it a moving window or just a moving maximum?

So, say the blocksize has organically (or artificially due to attack) moved to something ridiculous... say, 50 MB. 50 MB takes some time to propagate. Now, a miner can create another 50 MB block *or* create a smaller 1 MB block. I guess the question is effectively whether the lag created by large block propagation would be enough time for a small block maker to get a leg up. Because if the small block maker can pump out more blocks during the large block propagation (and subsequent block finding building on that large block), then there is an incentive for small blocks.

I apologize if that got rambly. I might have thought things and not typed them.