I CONSIDER myself uniquely qualified to comment on the performance credentials of the 2013 Cadillac ATS. That’s because I’m surely one of very few people to have owned a Cadillac Cimarron and a BMW 3 Series within the last five years.

What does that have to do with anything? Well, the Cimarron represents Cadillac’s misguided past, a textbook case from the 1980s of the wrong way to fight high-end European competition (in that case, by simply rebadging a front-wheel-drive Chevy Cavalier). And the 3 Series is the ATS’s contemporary muse, the car that Cadillac aspires to dethrone as the king of small luxury sport sedans.

While the ATS helps to banish memories of the Cimarron (and the Catera, inasmuch as anyone remembers that), I’m not sure it’s quite ready to erase the 3 Series as the modern reference for all-around sport-sedan excellence.

There are some areas, notably chassis tuning, where the Cadillac’s talents surpass those of the BMW. It’s in the totality of the thing, across the lineup of 4- and 6-cylinder engines, rear and all-wheel drive, where BMW’s decades of experience comes to bear.