We are not seeing the forest for the trees here. Lots of people do not have great balance. But if you are driving like crap, smell of alcohol, showing physical signs of possible impairment, then maybe your lack of balance will be an issue. However, we do not just pull random cars over and perform SFST's on them. If i pull you over for crossing the centerline and you don't smell of anything, and retrieve your DL and registration without incident, you will likely continue on your way without incident (ticket or not). I will have a pretty good idea of intoxication before I start my SFST's.I can see a potential problem here. It is entirely possible that the individual being so questioned could understand this to be a reference to a diagnosed medical condition. In my case, I have never been diagnosed with anything, but my sense of balance just isn't worth a damn.