“Tate Britain has been suffering an identity crisis for a decade, and is embarking on yet another round of therapy. The latest rehang of the collection is being billed as the beginning of an entirely new approach, scheduled to culminate in 2013 when a building programme gives it expanded gallery space and the entire collection will be displayed in chronological order. Yet if that sounds like a cure, the immediate arrangement pulls the patient to the very brink of catastrophe.”