Many years ago, I had a fairly highly modified Calibra V6 4x4. Came off a roundabout onto a long, straight bit of dual carriageway that I knew well. Early Saturday morning so no other cars around. Took it up to an indicated 165mph and then lifted off to slow for the next roundabout.
After the roundabout there was a few cars, so I returned to legal speeds. About 2 miles later, a police motorbike pulled me over. He said if I hadn't slowed down he would never have caught me. 
Anyway, his system measured my average speed at 137mph, and this was over a stretch after I had started to slow down!
That earned me a court appearance, a 28 day ban, and a £400 fine!!
Needless to say, my right foot is a lot lighter nowadays! 
Bloody hell, imagine if you did that now! The thought police would probably execute you there and then
Still, you could always lead by example and get your wife to take the hit, whilst lying about it and lording it up over the rest of us