A pretty damning analysis from Maddow.

Romney leaves up ads that have been proven false, despite saying the correct or remove things that aren’t true. When called on it, he reiterates the falsehood that got him in trouble.

Alternatively, he’ll say something, stake out a position (often a new one), and his campaign will pretty much immediately walk it back afterward, quietly, without saying even that it was a change of position, or even that he misspoke.

She gives ample examples of both.

huffingtonpost.com