Holy smokes! Reading this over, I'll bet there were more than a few injuries among the groups that practiced it. Imagine sending your kid off for a fun weekend and then watching them come home Sunday morning with an acute elbow injury from an arm bar... Scouting was dangerous enough without that stuff. You could get lost and even die in any number of unexpected ways. I watched a friend take a full swing of a wood axe…
Part of learning to defend oneself is getting injured along the way. It's part of the learning process. You can't learn to fight by reading a book about it. If you start to participate and learn through that participation, sometimes your efforts (or someone else's) will lead to injury.
Just to say that this is untrue, as long as your opponent has not read any books or had any training. A lot of scouts or just bullied kids who visit the library will tell you that.