Disclaimer: I imagine this query could also be primarily opinion-based and never very acceptable for this website, however there are a variety of technical misunderstandings that may be clarified together with it, so I am going to give it a shot.
There are numerous nuances concerned right here, and I concern that a big a part of them did not attain as a lot of an viewers because the change saying “we determined to not do it”. I imagine this was a poor selection of phrases, as the choice they made wasn’t whether or not or to not roll again the chain; solely whether or not or to not supply a bounty for doing so. I personally imagine it could be most unlikely that the choice would have really resulted in a deep rollback.
Let’s analyze the state of affairs from a variety of views.
If we solely think about miner’s actions, is it theoretically attainable for them to roll again the chain? Sure. When you’re questioning if there’s a small variety of mining firm CEOs on this planet, which, if all collectively satisfied, with full disregard for their very own monetary pursuits, the well being of the community, or authorized repercussions, might resolve to roll again the chain to a degree earlier than the theft, the reply is sure. That is the explanation why individuals care about mining decentralization, and permissionlessness of coming into the mining market. Nevertheless, except it isn’t only a majority of the hash charge that’s on board with this, however really near all of the community’s hashrate (a considerably tougher downside, as there are numerous small miners along with the few massive ones), this might possible have take days and even weeks (if it is near 50%), a time throughout which many issues can occur – together with a public outcry and a UASF-style fork to forestall the rollback from being accepted by the ecosystem. If thought of over a good larger timescale, occasions like this may increasingly even incentivize individuals and companies to grow to be miners, with a view to scale back the affect of enormous swimming pools.
Assuming miners maximize short-term revenue, would it not be financially attention-grabbing to rollback? No. Even when we assume that everybody within the community is appearing selfishly to attempt to maximize their very own (short-term) revenue, and ignores the protocol guidelines and the attainable repercussions from doing so, it isn’t. By the point the details about the theft grew to become recognized, the transaction was already confirmed a number of hours earlier than. Throughout these hours, miners had created dozens of blocks, which collectively earned a number of hundred BTC in subsidy and charges. The change would wish to supply a minimum of that quantity to the affected miners, to compensate them for the earnings they’d lose from rolling again these blocks, earlier than it could even be value discussing. Let’s name this the rollback value R. Because the stolen quantity was within the 1000’s (let’s name this S), that looks as if an inexpensive possibility. Nevertheless, nothing prevents the thief from utilizing (a part of) the stolen funds to do the identical. Each BTC provided by the change above R may be countered by an equal quantity provided by the thief. After which it turns into clear that the thief has the higher hand: the change can at most achieve S-R by a rollback, however the thief stands to achieve S by not having a rollback. A theoretical chance is a bidding warfare between the change and the thief, the place each enhance the quantity paid to make miners act of their favor. The top sport of that is that the change gives S-R, the thief gives barely extra and retains R, and miners are paid S-R by the thief, and no rollback occurs.
What would occur in the actual world? Theoretical fashions are attention-grabbing to review, however in actuality many extra sensible issues exist. I imagine these too are usually in favor of no rollback:
- Coordination between distrusting miners (particularly shut 100% hashrate) is difficult, and would take time. The extra time it takes, the much less advantageous a rollback turns into (see the above level), and the extra harm can be accomplished to the ecosystem (see the following level).
- An hours-long (in the perfect case) or a weeks-long (within the worst case) rollback would monumentally harm the ecosystem, and certain undermine the general public’s confidence within the system to the extent that it could severely scale back the profitability of many events concerned (together with miners and the change itself!).
- Even ignoring all of the above, miners will not be prepared to take a bribe to rollback due to authorized causes in the event that they’re publicly recognized (which they principally at present are). They might equally not wish to take stolen cash as a bribe, so this cuts in each instructions. This level turns into weaker if the mining ecosystem is extra decentralized, however that might additionally make coordination tougher.
- As I identified above, within the excessive situation the place such a rollback is definitely taking place, the general public has time to react. If a sufficiently massive group of economically related events within the community refuse to just accept the rollback, miners haven’t any selection however to go together with that. It is a last-resort possibility, and certain damaging to the ecosystem by itself, however it’s an possibility.
So to summarize: in principle there are completely methods by which a rollback might occur, and it is good to pay attention to these. In actuality, the safety of the system depends on financial incentives already that are nontrivial to investigate. It nevertheless appears most unlikely that within the case of a theft a deep rollback is an inexpensive final result.
