As Melinda notes, there was a lot of car talk at Mitt’s economic speech in Detroit on Friday. But in all that buzz generated by Ann Romney’s two Cadillacs, something was missed.

Mitt Romney, it turns out, has a secret past. At one point in his life, he had a dalliance with a sexy European.

No, it wasn’t Ann he betrayed. It was Detroit and the automaking industry that he so often mentions as he campaigns in his must-win home state. (“I love American cars, and long may they rule the world.”)

I discovered this episode as I was reading the excellent new book “The Real Romney,” by Boston Globe reporters Michael Kranish and Scott Helman.

The two write that when Romney was running for Massachusetts governor in 2002, his political advisers told him to keep a secret in the closet — or in this case, the garage:

One of the first things his campaign did was to make sure his BMW remained stowed out of sight. The image of Romney behind the wheel of a fancy car — and a European one, at that — was not exactly what advisers wanted in voters’ minds.

The car (or maybe it was a different one) makes another appearance in the book, as well — one in which Mitt has to choose between his devotion to it and his love for Ann. Not even close, though his reasoning gives a little glimpse into their most traditional of marriages:

Once Ann forgot to close the sunroof on a BMW coupe that was one of Mitt’s favorite cars. It poured, and the inside was soaked. But Mitt didn’t blow up. “I know who does the cooking here,” John Wright, a close friend, neighbor and fellow church member, recalled him saying. “I know who prepares my meals.”