Those time stamps are there for other reasons that may someday in the future be useful (like contract enforcements, or marking an anniversary, or something) It does not have any affect on the algorithms that govern the block chain.
Are you stating that timestamps aren't used to calculate the difficulty? Are you stating there are no possible manipulations of the difficulty via timestamps that could be exploited? If yes, where I can read the analysis?
Correct.
I went down this path a good while back myself. I even pestered a couple of the devs for a minute to confirm my assessment in the code.
If there is a record of that part, it would be in the IRC log, it was only a few lines. I didn't want to waste much of their time with it as it is only a matter of perception and not a technical problem needing to be fixed.
I wrote a few words about it yesterday.
https://bitcointalk.org/index.php?topic=789978.msg9039996#msg9039996If anything, that BCX pointed to it as meaningful, is less evidence of an attack, not more.
Does XMR still throw away 20% of the timestamps which are the statistical outliers when computing the difficulty?
So thus I could mine a chain with a much higher cumulative difficulty without triggering a difficulty adjustment.
Have you analyzed this genre of attack vectors?
Yes, XMR still throws away 20% difficulty anomalies, those timestamps are not used for determining difficulty.
Yes, if <20% of the blocks were at much higher difficulty within a 720 block sliding window, it would not trigger a difficulty adjustment.
Chain contention (which would be needed for a successful TW) is based on total sum difficulty, so it would essentially be a 51% attack that is stored up and then dumped on the chain all at once at a later date causing chain contention over which fork is longer, and grabbing all the block rewards for the stored period. It is defeated by checkpoints.
If BCX is running a forked chain with >50% of the hashpower of the live chain and maintaining that for 22 days in a sandbox, it is a grand waste of effort. We would also see nothing of it in the live chain.