This week we heard two ex-Fed Chairmen weigh in on the credit crisis – one of them a giant; the other a pygmy. Paul Volcker, the first of the two, is a giant in both the literal and figurative sense. By way of the yard stick, Mr. Volcker stands 6 feet 8. He stands even taller in terms of reputation. If ever there existed a Fed head willing to “take away the punch bowl,” it was he.