From Bitcoin's point of view, XT's "big blocks" don't exist, so the question of whether or not it can orphan them is moot. Core will continue to work on the longest valid chain, and that doesn't include any chain with blocks greater than 1MB in it.
That is not "Bitcoin's point of view". Please admit that there will be two (or more) implementations of bitcoin, each intending to be "the" Bitcoin. It is not objective or technically productive to decide from the start that the Core version is the right one, and the others are altcoins, no matter how much support each version gets.
I don't think it's helpful to refer to both the existing protocol and Mike's 8 GB block limit monstrosity both as "Bitcoin". It makes discussion difficult. When I talk about "Bitcoin" I mean the system we currently have, in which there is a blocksize limit of 1 MB. That Bitcoin is the own which doesn't see the invalid blocks.
Besides, the precise software that miners are running, what formulas they user, how they trigger the changes, what is their schedule for the following year -- all that is irrelevant. The only thing that matters is how many miners accept blocks greater than 1 MB, and how many reject them. So, instead of "XT" and "Core", it is better to say "big-blockian" and "small-blockian".
The number of miners accepting invalid blocks doesn't matter. Their blocks will be rejected anyway unless you're running the XT fork.
The longest valid chain accepted by Core *is* the longest valid chain, by definition.
Of course not; that is the longest valid chain *only for Core*. For implementations that accept bigger blocks, bigger blocks are (of course) valid, so the longest valid chain may be a different one.
And for implementations of dogecoin, dogecoin blocks are valid. What's your point? For Bitcoin core, 2 MB blocks are invalid no matter how many miners mine them.
Litecoin forked from Bitcoin.
Er, um, a mathematician would agree, I guess. Their blockchains share zero blocks, and zero is a number, too.
The software forked, not the blockchain.
It will not be easy to use the two chains independently, because all transactions are in principle executed on both chains. (That is another reason why they cannot be called "altcoins".) Only transactions that spend coins mined after the fork will be executed exclusively on the same branch.
The XT chain will quickly become polluted with outputs which are invalid on the BTC chain. "Taint" from coinbases generated only on the XT chain will fan out.
Have you read BIP101? It proposes jumping the blocksize limit to 8 MB next year, and then doubling of the blocksize limit every 2 years, for 20 years. That gives us 8192 MB blocks in 21 years. And that's what the sane bitcoiners should want?
Sigh, it wlll NOT give 8 MB blocks next year, nor 8 GB blocks 21 years from now. Those are block size LIMITS. Bitcoin had a 32 MB block size LIMIT for almost 2 years at the beginnig, but teeny weeny block SIZES. In fact it had a 1 MB size LIMIT since then, and yet the average block SIZE is still 0.45 MB.
It is sickening to see the small-blockians invariably replace LIMIT by SIZE in their arguments. Who is being disingenuous?
I wrote "limit" twice in the sentence you are complaining about.
If the block SIZEs ever get close to 8 GB, it means that the traffic is 15'000 times what it is today, which ma mean a user base of hundreds of millions.
No, it doesn't. Any miner can create a full block by generating their own transactions for free.
But I do agree that BIP101's schedule is stupid: it is silly to plan parameter changes several years in advance, when no one knows even whether bitcoin will survive to next year.
Good. Then please stop arguing in its favour. The sooner it dies, the better. We need to reject this and find a proper solution.
