It isn't so much that he has been critical of Obama, but that he has been completely uncritical of the market. The man likes to insist that all positive events in the past 8 years have been the result of deregulation as a means of freeing the individual. In essence, he sees the government as something which extraneous to the market, rather than essential to it. This lead to such gems as:
U.S. Economy: Sturdy as She Goes
Krugman's Depression Economics
and, the height of ideological indolence,
Tactical Nukes?.
The man is so wrapped up in free market fervor that he cannot explain anything except by saying "the government did it." And his inability to attribute Obama's victory to a collectivist mindset is just one more rhetorical contortion that betrays an inability to admit defeat. Like saying "They were right, but only for the wrong reasons"\."