‘THIS TIME,’ I THINK, AS I DASH through the rain towards the XJR-15, ‘perhaps I won’t put the headset on.’ Reaching the sleek, RAF-blue supercar I swing open the thin little door and then slide across about a foot and a half of sill and seat, slotting my lanky legs beneath the curiously shaped Nardi steering wheel as I slither in and shut out the weather. It’s an entry that’s easier described than done. Once ensconced, I feel like I’m sitting almost centrally in the car, not far from the driving position of a McLaren F1. Visibility is great and, surrounded by an airy, rain-spattered bubble canopy, I’m reminded of another supercar: a Zonda. The amount of bare carbon is reminiscent of a Pagani, too, although there is a considerably…