You couldn't do it in a road car, of course, because as it stands the outright lap record is a frankly astonishing 17min 11.572sec, held by current TT champion John McGuinness. He did the time on a full house Honda CBR 1000 RR earlier this year, and it meant that he lapped the course at average speed of, deep breath, 131.671mph. Which is, of course, totally insane and is way beyond the capabilities of anything four wheeled that wears a set of number plates.
The current unofficial road car lap record, for example, is held by ex-rally driver Mark Higgins, who drove a "lightly modified" Subaru Impreza around the course in a whisker under 20 minutes a year or two ago, at an average speed of "just" 113mph.
But what about the four-wheeled equivalent of the record-holding Honda CBR 1000RR? Something like a high downforce Le Mans car? Could that go faster around the fast but quite bumpy TT course, or would it simply fall off the road in the attempt?
Or, on the other hand, what about one of the triumvirate of new hypercars that has recently been unleashed – LaFerrari, Porsche 918 and McLaren P1; would any of these be able to summon enough speed along the straight bits and grip around the twisty bits to threaten or even beat the McGuinness record?
I personally think they could get very close. The Le Mans car would have the best chance, obviously, but because of the bumps and the weird cambers in certain places you'd be that much more likely to stack it in the attempt.
Which realistically means it would be down to the McLaren et al to step up and give it a go.
I imagine that anyone who rides a motorbike and has watched the TT, or seen the film TT Closer to the Edge, is currently foaming at the mouth in disbelief that I could even suggest such a thing might be possible. But I'm not so sure. So maybe we should try to find out. As they say, watch this space...