The original (black) stig was mainly ex-f1 (and the unluckiest driver ever) Perry Mcarthy. He did reveal all in a book which was one reason he was fired (the other being he wanted more money).
But there is no "one" stig. A lot of names have been mentioned before and they are probably all right. For example, just look at the build of MS dressed as the stig- its completely different to other episodes.
I've had the stig drive my old S2 190 round the topgear track and I can tell you know it wasn't MS.
It's just a persona so they can chop and change drivers due to scheduling conflicts and what not.
The MS lap was outstanding - 1:10 even in a barely legal race car is just stunning. IIRC that is faster than the caparo F1 which was removed as it couldn't clear a speed bump (be interesting if the FXX can).
Remember Renault turned up with a F1 car a couple years ago and clocked 59 seconds.
MS is a stunning driver - I've bee lucky enough to have a passenger rides in a Minardi 2 seater F1 car and you need to bear in mind they are heavier, have a longer wheelbase (not as agile but better high speed stability) and not quite as powerful (only by 50 odd bhp but 50 bhp is alot in f1).
Now hark back in the days of F1 when you had to be within 107% of the pole time to qualify MS took a 2 seater car *with* a 80kg passenger and would have qualified for the race. Even more impressive it was not on the back row either.
I know people say "its the car its the car" and yes to a large degree it is but there's no denying that MS is one of the best drivers ever (and I'm not even a MS fan

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