"Comity" as a reason to preclude class actions?

In June 2011, the U.S. Supreme Court in Smith v. Bayer held, unanimously, that the denial of a class certification motion brought by a plaintiff in one case did not bar a different plaintiff from seeking class certification in a similar case against the same defendant. That decision reversed an Eighth Circuit opinion and rejected the reasoning set forth in a couple of Seventh Circuit opinions in consumer class action cases. On Tuesday, in a case called Smentek v. Dart, the Seventh Circuit answered the question whether a district court, in deciding whether to certify a class, should "defer, based on the principles of comity, to a sister court’s ruling on a motion for certification of a similar class." The defendants' theory was that Smith v. Bayer suggested that comity was a basis for precluding "copycat class actions," but the Seventh Circuit said that this theory read too much into the Supreme Court's reference to expecting "federal courts to apply principles of comity to each other’s class certification decisions.” Rightly recognizing that adopting the defendants' theory would contradict the outcome in Smith v. Bayer, the Seventh Circuit held that "the defendants’ argument that Smith v. Bayer Corp. adopted a rule of comity in class action suits that precludes granting class certification in a copycat class action must be rejected."