Crankin, I think you are missing the point. Balance issue often are fit issues. Just because you have been professionally fit doesn't mean you were fit by someone that really understood the issue petite women face. Just because your body can comfortably reach the handlebars doesn't mean the bike will handle well. For example, if the stem and bars and are shortened rather than the top tube to improve reach, that can make the handling twitchy. I have ridden bikes that were so stable I could barely get them to turn (super high trail) as well as bikes with trails so small they were twitchy. I am the same person, yet depending on the the geometry of the bike, I too can have trouble taking my hands off the bars.