Logic dictates that there's almost always a direct relationship between an item's size and its worth; as the old saying goes, "the bigger the better." It's especially true with cars. Larger engines provide more power. Wider seats accommodate our growing butts. And personal buses (a.k.a. large suvs) carry us and all of our junk. However, every once in a while something comes along that defies logic, or at least makes a good opposing argument. Engineers of the 2006 Mazda 5, for instance, have taken a stand by suggesting that their vehicle can be sporty and offer utility and versatility.That puts those engineers on some shaky ground. The diminished minivan approach has been tried before, with less than stellar results. Does anyone remember the Nissan Axxess? How about the Mitsubishi Expo? We didn't think so. Nevertheless, Mazda is intent on tapping into a segment that has yet to be proven even exists in the North American market. If there is indeed the potential for substantial sales, the 2006 Mazda 5 has the styling and versatility to make a good go of it. But, if not, the Axxess and the Expo will be anxiously awaiting the Mazda's arrival into the Hall of Cars No One Bought.