http://www.youtube.com/watch?v=c6vTjaKdVoI

The leg cutting move I applied a lot during sparring was put to test with real sword.

http://www.youtube.com/watch?v=8cEAPjesoOg
Single handed cut.

http://www.youtube.com/watch?v=jrck8D17l38

Practicing solo wil drills in the padded sparring armor, showing that it does not hinder my movements any bit.

http://www.youtube.com/watch?v=mys5Z0EJD-s
A more clear version of the single handed leg cut, including following through action.

http://www.youtube.com/watch?v=U3ROpXK_JN8

Practicing cutting legs targets starting from crossing arms position.

http://www.youtube.com/watch?v=MJfcVhHHuXY

The leg cut from crossing arms position with corrected blade alignment.

How useful will this be against a skilled swordsman?!? Seriously, unless you had an overwhelming reach advantage, a simple step back and you can kiss your head goodbye. If you did have a reach advantage, I can just drop my sword point to block that shot as it's so slow with the squatting motion and just kick you in the face to push you over and then finish you off.

I don't know about Lancelot's technique but attacks against legs were used. There are references to them in Norse tales and from archeology, skeletal remains with severed legs recovered from burial pits. An attack to the leg would be a target of opportunity, like when the opponents guard was too high or he was off balance. I personally think that stepping in to attack the leg with a low cut would be better than squatting but I'm not that versed in sword sparing.

To quote somebody who hosts a lot of tourney:
"Johnny H

Lance

Thank you for posting these videos. There have been a lot of leg cuts landing in the HEMA tournaments and doing so against skilled swordsmen, with the attacker getting away clean. Some question if these would just be annoyance hits or would it actually take a leg off. It is good to see that someone is willing to test it out.


Steel Sharpens Steel
http://www.swordfightingschool.com/Tournaments.html
"

As for many techniques, it's all in the setup leading to that final cut... A technique taken in isolation is always easy to counter. The question is how much does the proper setup of the technique affects the cutting ability, which is difficult to test conclusively.

For my part, having been hit in the leg quite a few times even while determined to slip the strike, I think training to hit and defend that target is valuable.

Regards,

Well, the afore-mentioned armour and shields might make the leg the only real target, but a thought that occurs to me is that if you were in a battlefield situation and were careful not to hit your mates, then it might be a very good technique for dispatching an opponent who is occupied with your friends and their spears or something. Not sure what kind of armour and what not China had early on, but for a lot of early fighting cultures the upper body is armoured before the legs, making the leg a tempting target. Tag-teaming an opponent thusly might make a lot of sense.

I recall reading a research paper on medieval battlefield injuries and it was noted by the researcher that most of the edged weapon wounds were actually to the legs. Can't find the document for the life of me though, so take it for what it's worth.