That was fundamentally my critique of his EJW article in my invited EJW response, and subsequent research by Klein vindicated my position.
Now today in a guest Econlib post he confounds the point again.
Sure, when you ask normative or political questions economists disagree. Economists are (and I know some of you may have trouble swallowing this) human beings! We have different values. We have different priorities. We have different politics. So of course when you ask a normative or a political question we disagree.
But we're also scientists.
And that's why Bryan is exactly right to point out that there is a strong degree of consensus on positive questions. The heated disagreements among economists that exist (say, on the business cycle) are analogous to heated disagreements among physicists on string theory: in both cases we have too many models and not enough data to arbitrate (and in the economists case it's even harder because there's probably some truth in all the models.
Klein says he was "surprised" to see Bryan write this. He really shouldn't be. Certainly not after the intensive discussion over his EJW article.
That having been said, Klein probably does know this, he's just personally interested in the politics of economists. I'm not, really. People have their politics, but I like to keep the normative well segregated from the positive.