Of course, that's the difference. Heller dealt with defining the scope of an actual constitutional right that is actually in the Constitution. Roe dealt with a made up right.
Will's argues that because it is hard to define the actual constitutional right, the court should just punt. That is craven.
I don't see how he draws any valid parallel between a difficult interpretation of something that is actually in the constitution with the difficulties caused when the court makes up a right that isn't there.
Court's are there to interpret the Constitution, even when it's hard.
Of course, this whole post assumes Will's assertion that interpretation of the second amendment is 'hard'. Will's only evidence for that is that four left-wing judges interpreted the Constitution in the predictable left-wing way in Heller. Therefore, because they disagreed with the majority, the question is hard. That's a pretty slim reed. The four lefties on the Court rarely engage in a principled reading of the Constitution. Their Con Law is purely results oriented.
I scanned through parts of retired Associate Justice William Brennan's book (I didn't want to buy it and see money fall into his left-wing claws), and he gives a lot of credit to Felix Frankfurter, an appointee of FDR, I believe, as the instigator of a lot of the Court's "positivist" results-oriented legal logrolling and pettifogging. (Of course, Brennan didn't call it that.)