Quote from: thejaytiesto on October 13, 2017, 03:41:39 PM

So if your BTC ever went through a segwit transaction, even if you are holding it in legacy format address, it would still be vulnerable to this hypothetical attack?

As I wrote before, I think I remember seeing some comments at the logs for Trilema.com where someone there claimed that somehow the risk from the SegWit lineage could be removed, but I do not understand how that would be possible. Assuming a long-range chain reorganization then the lineage is double-spent as a donation to the miners, so then your descendant UTXO is invalid and must by protocol rules be rejected.

Additionally I introduced a separate theory, that those miners who know about this potential plan could be spending BTC for BCH (or other things), and thus plan to double-spend that BTC as well. So one needs to make sure none of that BTC is in the lineage, but how could you know which BTC that is. The kingpin over at Trilema had noted that he is trying to grok it all when someone showed him my theory. So in that case, any BTC that was acquired since perhaps late July might be vulnerable of being removed from the BTC blockchain.

Additionally what if they transferred BTC to exchanges and will double-spend that? It could get real messy. Exchanges could possibly be bankrupted, perhaps especially targeting their enemies?

This is why I have refused to buy any BTC, nor keep any crypto on exchanges (use only ShapeShift for trading and Localbitcoins or Rebit.ph to cash out), because I do not think any software can help you acquire BTC safely at this time.

I am waiting for this mess to be sorted out. I hold only LTC and BCH at this time, although my group also holds 100s of BTC that was acquired a long time ago and thus are safe.

I am not that knowledgeable about your other questions. No, I have never tried the TRB client. I havent even had the spare time to go over to the logs and chat with those guys yet.

Once again, its possible Im Chicken Little. So every reader should decide for himself the threat level he/she perceives to be reality. Im not trying to sway anyone to do anything. Im just sharing my thoughts and discussing.

@CoinCube noted about this threat that if it came true, then users who inadvertently double-spent BTC could be sued by exchanges and others and funds clawed back making everybody in the lineage chain responsible for the double-spent funds. A huge mess! That is why he thinks miners will never do it. He thinks there would be outrage in the community. But the whales, most of which who presumably know about this risk, have I think prepared. Its the n00bs who are likely to be harmed and theyre not economically relevant anyway, their UAHF/community vote is not superior in the context of an economic majority. So being that I view myself as a defender of the honest underdog, I feel obligated to share this information.

EDIT: I found the Trilema logs where they were discussing my thoughts and where he mentioned that you can bury a segwit tx into legitimate spending which is deep enough to not be practically reorg-able. Now I perhaps realize what he means is that if your lineage has descendant UTXO which fork out to UTXO which the miners own (which is worth more than), then theyre unlikely to revert (and double-spend) that lineage. Or simply because the miners do not want to wreck too much havoc because this would make their rollback too unpopular. So he also means that if you can mix your activity in with the spending activity of whales, the miners are unlikely to revert the transactions of whales as that creates resistance to their fork.