Why have they never learned how this works?

Brian Beutler, just... look, no.

But after that, I think there’s a good chance that the legislative assaults against the ACA will stop. That all depends on how smoothly the roll out goes. But if enrollment goes as planned, and the problems are minor and temporary, the whole question of repealing the law will take on a completely different character than it has right now. Right now, repealing the law entails rescinding some real, but fairly ancillary benefits. After January 1, voting for repeal will mean voting to kick a small country’s worth of people off of their health insurance.

That’s a bad vote to take. I don’t think Republican leaders are going to be super eager to take it. If that’s right, then the fight over Obamacare will change overnight. And that’ll be the first major political consequence of implementation.

No. That's never how it works. Republicans will gleefully "kick a small country's worth of people off of their health insurance" because that's what they do.  Then they will turn around and say these same people now have no insurance because "Obamacare failed" and this will be a winning argument. A lot of people who are currently angry at Obama will gladly accept a new reason to continue in that anger.