Jay Merrick: Out goes Oswald Boateng, in come Gieves & Hawkes

Herzog & de Meuron's proposed Tate Modern extension is almost an original piece of architectural design but its form has been simplified since the first version of the scheme was presented. And even that version – a giant tectonic logjam erupting upwards from the edge of the Thames – resembled the practice's design for a Swiss pharmaceutical company headquarters. Art, of course, is as much a drug as Viagra or ecstasy; and so is headline architecture.

The new design seems carefully tailored, more Gieves & Hawkes than Oswald Boateng. Yet the shadow of hubris falls across it. Once, over lunch with Jacques Herzog in a Basel cafe, he bridled at talk of architectural virtuosity and buildings as chunks of glowing iconic phenomena. "It's bullshit," he fumed. "It doesn't make sense. Only the conceptual artist can survive. The others are watchmakers, presenting their architecture as a brand, like a new watch that comes out in the Spring."

The form of the proposed extension has certainly lost some of its conceptual chutzpah and will make a less striking brandmark than the first scheme. There is also thequestion of the building's contribution to its urban context. The first scheme had little to do with it, although the new one's relationship to its surroundings is slightly better. But, then, context is almost always the fall-guy in large scale "iconic" architectural projects.

The building won't be conceptually shock-of-the-new, but it will demonstrate what Herzog describes as "the maximum thing" in the texturing of its facades. It will glow, and it will be phenomenal. Yet it will also be a superb visitor experience and the most finely crafted big building in London since Eric Parry's elegant office tower in Aldermanbury Square.