> So by the time the 2x fork comes up, the segwit-enabled chain will already be in use for several months.
Correct. But there's an asterisk here: most people (78%) are running bitcoin core, some run Core/UASF (5%), and some run bitcore (2%). Together, that's 85% of nodes. Core 0.14, Core/UASF, and bitcore are all compatible with segwit, but not with the blocksize increase. Even if you wait multiple months, if people stick with Core (a possible outcome) then they will see 2x blocks as invalid.
> That sounds as if the minority chain could become effectively unminable for the rest of the difficulty period.
The chain wouldn't be unmineable, it would just get mined slower (mining profitability wouldn't be impacted for miners staying on the chain provided the price stays the same). But you're right, blocks will come slower, throughput will be lower, and the adjustment will take longer.
> So by the time the 2x fork comes up, the segwit-enabled chain will already be in use for several months.
Correct. But there's an asterisk here: most people (78%) are running bitcoin core, some run Core/UASF (5%), and some run bitcore (2%). Together, that's 85% of nodes. Core 0.14, Core/UASF, and bitcore are all compatible with segwit, but not with the blocksize increase. Even if you wait multiple months, if people stick with Core (a possible outcome) then they will see 2x blocks as invalid.
> That sounds as if the minority chain could become effectively unminable for the rest of the difficulty period.
The chain wouldn't be unmineable, it would just get mined slower (mining profitability wouldn't be impacted for miners staying on the chain provided the price stays the same). But you're right, blocks will come slower, throughput will be lower, and the adjustment will take longer.