From the start, the Turbine Hall at Tate Modern has been unusual. Taking its name from the function of the vast space when the building was still a power station, it’s really not a typical museum space. The artists commissioned to make work for it have all responded to it in very different ways but it’s the response of the audience, almost as much as the work itself, that makes the annual Unilever Commission fascinating. From Olafur Eliasson’s The Weather Project (which I’ve written about before) to those brief few days when visitors to Ai Weiwei’s Sunflower Seeds were allowed the access the artist had intended before health and safety concerns caused the work to be cordoned off, the Turbine Hall somehow makes people behave more like they would at the beach than in an art museum. All of which makes Tino Sehgal (whose work I’ve touched upon before elsewhere) an intriguing choice for this year’s commission. How would an artist whose work lies in the dynamic between audience and performer make work for such a cavernous space? And how would the audience respond?