One of the things that would be helpful in answering the question is if we knew what, empirically, a "policy view" is. Let's say one lawyer believes the constitution allows an abortion and the other doesn't. If a judge is asked to decide this case, what is an example of one using a "policy view" versus using a "legal view," or using a hybrid? Because it seems to me that this whole way of talking actually does something that it doesn't advertise: it sets forth a normative criteria for "legal." It says, e.g., that formalism is "legal" but sociological jurisprudence is not. Or that originalism counts, but not living constitutionalism. Or perhaps it says that judges who feel sad when they decide "follow law" while judges who feel joyous do not. All of these suggestions fail, of course, because they seem to want to say that casuistry performed by American judges is sometimes legal and sometimes not. You can't really say this. All that can
properly be said is that some casuistry is GOOD, some not.
What I am saying is that the question is both loaded and normative. It would be like asking whether cooks eat good or bad desserts. And then asking of those who are eat good desserts, whether culinary education helped.
Dworkin suggests that justices seek integrity in their casuistry. Might it not be more honest to ask (of your concern) whether there is authority to say that legal education helps judges develop better integrity in their work product? Or might it be more useful to ask not what "policy views" a judge has, but what epistemology his or her framework displays, and how this can be linked to intellectual development?
Your work, of course, is probably the best political science ever produced on the subject of jurisprudence (I don't call it behaviorism in this context). Indeed, one could read Ronald Dworkin and then Larry Baum and not subject the the mind to any major confusion. I remember once feeling this way in graduate school. But there still is the nagging question of why one should not encourage political science to: (a) stop chasing evidence of ghosts; and (b) start using language sets that are more useful.
There is no such thing as a "policy judge" because there is no such thing as an illegal opinion. There is only good and bad casuistry. The only thing one could ever look for is integrity in the product.