Kyle Cooper in Paul Rand: Modernist Design by Franc Nunoo-Quarcoo (no relation):

I heard Paul Rand’s voice approximately 18 months before I met him. That is to say, I heard Hugh Dubberly doing an impersonation of Peter Levine doing an impersonation of Paul Rand…. “You are doing that raised-pinky design,” Peter [said], in what I now know to be a slightly-more-accurate Rand dialect. […]

We wondered aloud if he had ever collaborated with another designer. “I would, but Jan Tschichold is dead,” he told us. We quickly familiarized ourselves with Jan Tschichold’s work, which was refined, and found a picture of him where his pinky was, in fact, raised.

So it seemed that it was OK to be decorative, and it was OK to be rigid; you just needed to do it brilliantly. It was clear to me that Rand was right in saying “An idea is only as good as its execution” and “Form is an idea.” Bad form, then, is a bad idea.