Hi BOL1OX and boxtops.......I had thought that this thread had come to its end. However, I am pleased that friendly folk are taking the opportunity to contact each other. Perhaps therefore I can throw in a few further comments.
If helicopters were being tested, I'd go along with the thought that the Stig might be Noel Edmunds who does pilot his own machine.
Michael Shumacher did appear as the Stig in one episode of Top Gear; having driven his own custom-built Ferrari FXX around the test track..............It's all there in the following:-
http://en.wikipedia.org/wiki/The_Stig
Ron.
PS Stig backwards is what the presenters are :-)