The only thing stopping amir kahn being a knockout puncher is his weight. He weighs roughly the same at the weigh in and the same on fight night as his opponents. Supposed KO artists like Miguel Cotto for example have a distinct weight advantage come fight night. Something like a 14-18lbs advantage. Thats their extra power right there. Amir has got plenty of time to grow into power, he's only 19 and he's stil growin.