Politico's piece is interesting. If Larry Summers and Glenn Hubbard were members of Congress, would we have "better" tax policy? If climate scientists ran the Energy Independence and Climate Change Sub-Committee, would "better" policies emerge? For example, would we be more likely to have a carbon tax now? The Arrow Impossibility theorem would appear to be relevant here. Would self interested Representatives listen "to the experts"? Or would they politely listen and then vote their self interest?
When do experts improve policy design?
My answer is simple. If we agree on the goal, for example --- if we agree that we need a military weapon to defeat our enemy then a Manhattan project takes shape and the nuclear bomb emerges with high probability of success. If we agree that our goal is to achieve 4% economic growth, then the experts can figure out how to do it. If we agree that our sole goal is to reduce the cost of entitlements then the experts can figure this out.
But, if we don't agree on the goal --- then I'm not sure that having the experts on the inside cooking up the legislation makes a big difference.
So, in my vision of democracy --- the messy process sets the goal and then the experts decide on what is the cheapest way to achieve the goal. Again, if we haven't set the goal and we disagree about the goal, will having experts on the inside matter?