I believe the reason they are considered dangerous is because most people are very new to them. Shoulder locks are dangerous for 2 people that are inexperienced in them. NAGA leglocks at the lowest experience division. If you look up the injuries for the past few years of NAGA, it's all shoulders, elbows,necks...leg injuries are so far down the list. Takedowns are dangerous for 2 rookies also.. So you see my stance on the "dangerous" topic.
Barncat and I have been repping, landing, and teaching the russian knot series for many years. (You notice Barncat eating up the local experts division with it). I personally love kneebars and slicers also. Many locals schools have considered us a leglock school but we really do NOT focus on it. It's a part of the system just like everything else. You get taught the knot series when we are teaching it that day. I do kinda consider the knot to be an intermediate position. We definitely don't let people finish heelhooks in rolling. Barncat and I finish them on each other, but not the students. The heelhook is tricky, it doesnt hurt until its way too late. experience is the only way to do them safely. With that said, We embrace leglocks just like any other part of the game and a have the safest gym in our area.