We've just been watching the coverage of Beyonce at Glastonbury, and I was surprised at how much she and her backing dancers looked like they were doing some weird kind of human dressage. Perhaps it was the combination of impractical shoes and potentially crotch revealing leotards that made them wary of taking steps that were too large, but whatever their reasons the overall effect was pretty peculiar. I was, however, impressed at her knee sliding action which, contrary to my personal experience, didn't seem to end up in scabby blisters and bruised kneecaps.