I’m with bakes on this one. I’m pretty sure that the main reason his ‘identity’ has been kept secret for so long, is because he is in fact not one person, but several, over the last few years. They’ve used several different racing drivers, and just dress them up the same. Cheaper than hiring one, who then gains celebrity status, and starts wanting more and more money. Plus, with motor racing being quite dangerous, having several Stigs would be good insurance if one gets crushed or mashed. They can just substitute another. Likewise, if one’s off having a baby or something.
This bloke is probably just the current Stig.