Bush was excoriated because he couldn't tell the MSM about mistakes he had made. Obama does not recognize the possibility that someone who stopped the oceans from rising could ever make a mistake. Conventional wisdom has Bush as an idiot, Obama as a genius.
Mitt Romney also has a reputation as a smart guy, moreover one who understands business and finance. He has an easy path to turn a mistake into a benefit. He could say, "Federalism is, among other things, about the idea that individual states can serve as venues for policy experiments. I led Massachusetts in such an experiment: I was instrumental in designing a state mandated health insurance system upon which Obamacare was modeled. My plan has been a disaster for Massachusetts.
Ironically, that lesson was made possible by the vestigial Federalism which President Obama seeks to finally destroy via initiatives like his own health care mandate. I am able to learn from my mistake, so should the country.
The broader lesson is that central planning cannot replace the free market, no matter how smart the central planner thinks he is. I will not forget that again."
Since Romney apparently cannot do this simple and intelligent thing, I'd agree with this analysis.