If there is a fork, than XT has already won.
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That would be the case of reaching complete consensus with the economic majority. AFAIK 75% (needed by XT) will cause a noticeable split, and thus this can be achieved.
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There will be a period of time in which this will be possible to do. If you think that everyone will switch (all miners and merchants) the first day after the fork, then think again.
I don't think, there is an economical incentive to keep on the weaker chain. I think, it will be settled by businesses, who want to make a revenue and they just take too much risk, when they stay on the weaker chain.
I don't think, it will be settled by ideological incentives, once the split has already happened.
So, the only interesting question here is, IF the split happens.
(And I think, all this "doubling you Bitcoin"-business is just a wet dream)