The Supreme Court's momentous decision on the fate of President Obama's health care law is likely to be dry, sober, weighty and self-conscious about its place in constitutional history. The arguments in the case, held exactly three months ago, were something else entirely. They illuminated the work of a court that takes a distinctively loose and even lighthearted approach to adjudication. A timely new study, based on an impressively detailed review of the transcripts and audio recordings, revealed an exceptionally garrulous and jocular bench.