The problem is that, as I tried to explain, there will not be a "Gavincoin" and an "Adamcoin".  Even if the chain splits, and the 1 MB branch survives for a while, there will be just a two-headed bitcoin. Even if you could trade and speculate on each coin separately, you cannot attack one in the market without harming the other. 


I cannot avoid being the comp sci prof here.  Technically, what Gavin and Mike say is right, and increasing the limit is necessary for two reasons that can't be ignored:

* With 1 MB limit, it is already too cheap and easy to carry out a spam attack.  A attacker with 10'000 USD budget could probably delay half of the legit traffic for days; an such an attack will get easier and cheaper as time goes on. With 8 MB limit, such attack would be at least 10 times more expensive for the attacker.

* Congestion would make bitcoin unusable for ordinary e-paymets.  The user base will stop growing; users wil be turned away not just because of fee increase, but mostly because of the long and unpredictable delays. 

In contrast, for these past 2 months Adam has been only spreading baseless FUD and ad-hominems.  For one thing, he always says "size" instead of "size limit", then claims that 8 MB blocks will have very serious effects (first it was on full node count, then on orphan rate, then mining centralization...) but does not offer evidence or numbers.  At the same time he ignores completely the two points above.  He promises that the LN will provide the growth that the 1 MB limit denies; but the LN will not work, and will not be bitcoin...