I have never had a blowout day. However, I have occasionally planned to eat a small portion of something I don't normally eat -- for example, a small piece of pumpkin pie at Thanksgiving or one piece of chicken with sweet barbecue sauce on July 4th -- and that has not created problems for me. My intuition tells me that if I went overboard with the carbs -- for example, eating the potato salad and ice cream in addition to the piece of barbecued chicken on July 4th -- I would have trouble getting back on track.