Blanche wrote:

The only justification for a groin kick is immediate danger.

According to a self-defense class I once took, you should never try for a groin
kick. The prospective victim reacts instinctively to defend this area, so it's
actually very difficult to connect. If you do connect, the pain is delayed a few
seconds, and the now-infuriated victim is very likely to do serious damage to you.

The instructor recommended that you kick the knee joint instead. It's much
easier to connect there, and the joints are fragile and not designed to be bent
backwards. Best of all; if you connect, the victim is immediately incapacitated.

George Patterson
Coffee is only a way of stealing time that should by rights belong to
your slightly older self.