ping
History, of course, teaches us that Pollin and Ash are wrong. we only need to look at the total failure of the recent "stimulus" to know this to be true. Unfortunately, this is what is being taught in our institutions of higher learning today, and Paul Krugman is held up as a maven who must always be believed, no matter what.
We'll get what we deserve.
Bump
It's actually not all that hard, if one is more interested in predicting how people will react to policies than in justifying the policies one wants. The simple principles, rules, and models taught in Economics 101 work very well for predicting people's behavior. Many more advanced models which try to explain why those rules don't apply in various situations are often less accurate than the simple models for the simple reason that the rules continue apply even when they proponents of those "more advanced models" don't want them to.
Interestingly, the more advanced models have even more trouble predicting future trends than present behavior, but even simplistic evaluation of incentives often allows accurate prediction of trends even for things which are hard to directly measure. For example, one needn't measure how many people do X today to know that a policy that makes X profitable is apt to massively increase the number of people who do it. If the cost of the policy is proportional to the number of people who do X, any cost predictions which are based upon the number of people doing X today are going to be far less accurate--even if the number of people doing X is known precisely--than predictions which figure the costs will grow without bound unless or until the policy is rolled back.