Mels Crouwel, the lead architect for the Stedelijk, was government architect for years. His firm is normally reliable, with an industrial bent. He promoted the tub as a technological novelty, its aerodynamic exterior made of a reinforced synthetic fiber coated in white airplane paint to give the museum a shiny, enameled finish and to nod to the old Stedelijk’s white rooms, which still fails to explain the plumbing metaphor or other moves. — NYT