I have a Red group on one of my bikes and occasionally I will try to make a shift into a larger gear and not push the lever all the way through to the second click and it will downshift into a smaller gear. This usually happens at the worse possible moment. In theory and on the internet, this should never happen, but in the heat of the moment, when you are 40 miles into a fast paced ride, tired and hurting, things don't always work out according to plan. The rest of the time I love it.