I have experience of this in the Glasgow half this year. Was catching a group for the last couple of miles and there was one lady in the group. Over those couple of miles she had managed to break from most of the remaining men and I was picking them off as well. So we come into the last half mile and I actually catch up with her, thinking to myself that I have enough in my legs to sprint past her, but unbeknown to me this lady is actually Holly May, a GB international half and full marathon runner, she feels me on her shoulder, steps on the gas and leaves me for dead!!