Mr Senna, however, had other ideas and simply pressed the pause button. This facility, denied to you and me, allows the finest drivers in the world to slow down the action to a more manageable speed and, in the case of a fast-moving NSX tail, stop it altogether. With a twist of opposite lock and just the right amount of throttle, it slid no further. It didn't come back; there was no need. It just hung there in a state of suspended animation, a few degrees off line, waiting until the nose kissed the rumble strip on the apex before snapping straight as we swept back towards the pits.

I don't know how fast the NSX took that evil, drenched corner, but by the time I had got a grip on myself and my eyes back on the speedo needle, it was hovering above 90. Senna remained expressionless, and if he reads this I doubt he will even remember.

It's something I will never forget. But my laps with Senna weren't all like that. On the contrary: on the first lap the world champion trundled through corners at speeds I could match, chatting away, eyes shining. Patiently, he took time to talk me through the differences between the old circuit and the new.

Apologising for not having completed enough laps to make a proper evaluation‚ he nevertheless seemed to have committed the entire track to memory in considerable detail. As we enter Copse, the first corner past the pits, he observes: "You turn in earlier here and it's much faster now. It used to be smooth but now it's very bumpy."

Beyond the next short straight and Maggotts curve, the track jinks left, right, left through Becketts and Chapel. In his McLaren, Senna takes all of these in fourth, which he says is "quite fast". Clearly he is not a man prone to exaggeration.

Even so, "you exit slower than before and that lowers the speed you can achieve down Hangar Straight." As we exit Chapel onto the never-ending strip of tarmac, Senna says with considerable relish: "You need pure power down here," as if to recall pointedly the traditional overwhelming superiority of his Mclaren-Honda in this area, so notable by its absence this season.

I suggest that the right-hander at Stowe looks much the same as before. "You're right to a point. Everything is exactly the same until here, it tightens."

Simultaneously he hauls the NSX on to the new line and we head off to Vale, a sharp left which is governed by handling and driveability. "It's very tight and that makes the next corner [Club] slow. You used to be in fifth gear; now you start in third and go through in fourth. Speed down the straight to Abbey and beyond is governed by how fast you can leave Club and it's slower than before. You still go through [Abbey] in top but you use shorter gearing than before which reduces your maximum speed".

Bridge sees Senna digging deeper into his understatement sack, describing it as "a new corner taken in fifth gear, which is quite fast." Even though I know that means 150mph or more. Then the circuit slows you down through the increasingly tight Priory, Brooklands and Luffield, by which stage speeds are so low that it's impossible to approach the once notorious Woodcote fast enough to make a corner out of it.