Groin Kick Technique

The first thing is stick your hip forward then lift your knee up then the rest of the leg comes up with a quick snap.  This technique should be practiced on partners who have different height.  

Closest Target

This is another skill that's necessary to practice and should be combined with accuracy training.  When you train with a partner take some time to practice finding the target closes to a weapon for example kneeing to the stomach or hip, punching to the jaw or side-kicking the lead-knee of your opponent.

Taekwondo Flaws

Taekwondo is only good for sport the style has too many tricks in it's kicks and their no where near being good for self-defense.  If you were to remove all of the unnecessary techniques their wouldn't be much left to use.  This style is one of two styles that are used in tournaments where the rules don't allow punches to the head...if they wear head gear then why not.

Kicking Them When Their Down

There's nothing wrong with finishing an attacker off when he or she is down and you know if you don't then they can get up and fight you again.  It's best to not assume that the attacker is seriously done and walk away without thinking they may have a deadly weapon.  All you have to do is stomp-kick or soccer-kick the head once or twice without over doing it then run while watching your back to safety and call the cops. 

Low Round-House Stopped

A good defense against this attack would be a front stomp-kick to block it or you can simply use footwork and back away quickly. Don't try to use your hand to block this kick that would be very stupid and keep those hands up.