Even though this battery is less than a year old I've had some problems with it. The positive cable tends to come loose and then it won't start, even when all the lights and radio work. I have to them twist the cable to make better contact with the post. When I go through this exercise I don't loose enough power to drop the presets or clock. I just re-tightened the nut in the connector when I get home. I've never had this problem while driving. You might be on to something here. I'll check the tightness of that cable.
I might experiment to see if when the car is running and I disconnect the battery, will the car still run? Or can anyone answer that for me?
Thanks!