People have been saying that Wayne McGregor’s new Woolf Works has reinvented the three-act ballet, but not so. William Forsythe reinvented the three-act ballet 20 years ago with Eidos: Telos, a mesmerising masterpiece that I found myself recalling as I watched the McGregor. There are many formal similarities: the search for sense through words, the woman facing darkness and death, the central act in period costume, spectacular light, video, ambitious structures on stage, and so on.