Hmmm, I had always thought of leg kicks to be an excellent self defense tool.

Someone with years of kicking experience developes tougher shins and can actually target very low on the shin or calf of an opponent. Shin on shin kicks are extremely painful. Even a small tap will be excruciating to an untrained aggressor. Also such a low kick does not require a great shift in balance or allow a large opportunity for a takedown of some kind.

An extra bonus is the relativly meager social and legal response I would expect from this strike as opposed to others (I work as a bouncer so this is of utmost concern). Ex. a punch to the face will look worse to the police (not to mention you risk breaking your hand), and to any of the aggressor's friends who will now surely join in the altercation. Kicking someone in the leg looks less severe and would probably have a lower chance of anyone calling the police. Christ even the guy who got kicked would be too embarrassed!

But I'm actually pretty green in standup. That had always just been my thought, especially after nearly crying like a little girl after a light shin on shin tap.