I have never thought about that but it does make logical sense. You're probably right! I have been doing this for the past 6 to 7 years. I thought being the front heavy as most front wheel driver vehicle are and most of the breaking power (~60%) are in front so stopping distance would improve and I can tell the difference. The fact that back wheel will spin around is logical only when you turn. I agree 4 wheel winter tires are better than 2 and I still think 2 is still better than none base on my winter exposure. I guess having 4 wheel ABS on the car make a difference in controlling the car during braking.