I certainly don't think the Obama team did everything right on the economy, and I also don't think they did everything they could. Discussion of the size of the stimulus is always central, but they had a lot of power to deal with the foreclosure crisis properly (even a giant fund they didn't use) and they just let the banksters get away with stealing homes. I'd guess fixing that would have improved the recovery a bit.
But Krugman's correct that people playing the "should have focused on the economy not health care" game never say what exactly that means.