My english is not that good so I`m not sure what you meen whit a ACL-Tear. Anyway I think you maybee pictured what I was trynig to expalin a bit wrong. What I`m saying is that you would be a fool to try taking the landing all with your legs when the cliffs get realy high, it does not work at all. Not only do you prevent yor legs breaking in a thousend pices, but landing from high cliffs you need to slow down your speed to, and letting your butt go into the snow is a good way of doing that. I`ve dropped from quit a few cliffs in my life, many over 10 meters high(35 ft), so trust me, I`ve got some "know-how".