Will gavin and Mike visit each miner, put a gun to their head, and force them to switch to XT. Explain what mechanism they will use to force miners and users to upgrade to XT against their will.
While not directly relevant to the mechanism in which XT plans to introduce itself, here's a snippet from earlier times (back when it was still '20MB or bust') that would still apply if miners ended up being dishonest (e.g. voting for larger blocks and kicking in the mechanism, but not actually processing them - let alone mining them).
Couture: I mean, if we extrapolate... if most companies that you've talked to are on board with this - with switching to Bitcoin XT - then what you're saying is essentially that this is gonna happen, this block size increase is gonna happen, no matter what.
Hearn: I think so. The only question is: how long does it take for people to, y'know, opt in? Do we really have the majority that we think we do? I mean, you know, from polling, you know, going and talking to, you know, important players in the ecosystem we think we do, but there's nothing quite like measuring it for real.
Couture: Mm-hmm
Hearn: And then, the worst case scenario is: the majority of - the economic majority, that we call it - is in favor, but the hash power - mining - majority is not. That would be a very messy situation for Bitcoin.
Crain: So, can you explain that? How would that happen? So you mean that, like, let's say Coinbase and the big companies and they're all in favor, but the mining, uhmm..
Hearn: Yeah, so let's say that, uhm, you know, so that those.. there's been some concerns raised by mining pools in China, for example, where there's a lot of mining going on that.. their connectivity is extremely poor, to the rest of the internet, for a bunch of reasons. So if the needs of the wider global Bitcoin community start diverging from what, you know, miners in China want, then who wins? The answer is: the economic majority wins, right, the wider community wins - but it would require a bit of, y'know, a bit of a technical mess to sort everything out in that case.
Crain: Because you somehow have to get, uhm, clients to ignore, potentially, the longest chain...
Hearn: Yeah
Crain: ...to only accept Bitcoin...
Hearn: Yeah. So, people - again, merchants and exchanges sort of be running Bitcoin XT. If we imagine this sort of worst case scenario happening, they would ignore the longest chain - doesn't matter that it's the longest - if it's, uhm, y'know, well, no let me rephrase that.
[concurrent]
Crain: They would, they would take the longest chain...
Hearn: They would be forced
Crain: ...with that specific version of the software, right?
Hearn: Yeah. So let me rephrase that. Right. If miners deci...were building a longer chain than the 20 mega chain then, you know, the client would keep switching back to them and keep ending up with this bigger and bigger backlog. Uhm, and at that point, what we would have to do is, like, checkpoint blocks into both the full nodes and the SPV wallets, so that's a much larger and more complicated upgrade, uhm, to force it onto the larger chain, right. And in the worst case scenario, if the miners and the rest of the Bitcoin community end up in some kind of, like, full-fledged war, that would basically wreck Bitcoin. So, we would hope that miners wouldn't do that. Of course..
Crain: Yeah...
Hearn: ...it's not in their best interests to mess up Bitcoin for everyone.
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