To allow a kid to be hard on himself is a lot different from allowing your child to be a bad sport. There still need to be some parenting done if your child is throwing headgear, throwing fits, or is just a bad sport. The "being hard on yourself" part starts when you walk off the mat. A friend of mine a few posts back on this topic said her son is hard on himself when he loses and he is, but I have never seen him be a poor sport when it came to shaking the other coaches hand or congradulating the winning wrestler. Your child has to know what behaviors are accepted on and off the mat. Be the parent, not a bystander, when these behaviors are being learned.