I did try and wave and flash my lights back, but a combination of:
1) pouring rain
2) lack of traction
3) My mate in the TVR trying to catch the others GTR/R8/XK/Exige/Z4
4) Utter surprise at seeing another Aero

I managed to turn off the wipers instead of flash the lights, leading to near instant lack of visibility and panic…..I did try and wave, but there was a lot going on in my car at that bend/point in time. Sorry. blush