Well, don't get too excited.
First, was there really any doubt about the gay marriage decision? Some of the coverage I read referred to Kennedy as a "swing vote," and that kind of annoys me. It may be true in a lot of cases--certainly (and famously), he changed the result in the Planned Parenthood v. Casey case by changing his mind--but at this point his position on gay rights is clear. He's been writing the Court's gay rights opinions since what, 1996, in Romer v. Evans? He was not a "swing vote" in the gay marriage case. (As a general matter, this annoys me about how people talk about Kennedy. He has been on the court for decades now and he has clearly-defined views on most issues. I think he is rarely a "swing vote" any more.)
As for Obamacare, let's keep in mind that Roberts is a really conservative guy. His dissent in the gay marriage case is evidence of that, for anyone who thought he was going to start veering left a la Blackmun/Stevens/Souter. But he believes in judicial restraint, the King v. Burwell case was clearly aimed at frustrating the legitimate action of a duly elected legislature through the legal process, and a good judge should be very, very cautious about approving that kind of thing. Additionally, he is very cautious about doing anything as Chief Justice that would jeopardize respect for the Supreme Court and spur cynicism about it as an improperly political, rather than judicial, institution.
Not to dampen your excitement about the decisions themselves. I guess what set me off was just your word "intractable." Most of the judges absolutely are intractable. Nobody moved Kennedy and Roberts to the positions they took this week. They are very smart, serious judges--and they're basically conservative, make no mistake. Liberals just got lucky last week.
