supthecreek said..SupChickadee said..I've been toying with the idea of posting a question about leg ropes that i would appreciate advice on, but this thread is pretty relevant - tore a medial left knee ligament supping in Bali last November when a late take off went wrong and got rolled in the white water badly when i got flipped around and dragged backwards by the sup.
My details fifty something aged brood mare at maybe 70kg fully wet and wet suited up, 9'6 sup for this particular break as its 1km off shore, with a knee leash on right knee, natural stance.
What happens in powerful waves is i might dive into a breaking wave head first (yes i've let my sup go behind me, but no one is behind me), so i've dived into the water, but the drag of the sup flips my body face up, with my left leg getting dragged around and i get dragged backwards by the leg rope. Doesn't happen in less powerful surf. Even if i tried to kick the sup over the first wave, as mentioned earlier in this post, if its a set of 3 the 2nd and 3rd wave will get me anyway.
Talking to a friend he uses his paddle as an anchor which i will try and see if that helps, but i wonder if using an ankle leash might make a difference (although previous posts suggest there are issues with both knee and ankle leashes).
I now bend my knees in the white water so that my limbs don't get flipped around like a rag doll, which helps but the knee still might not be good enough to go out in 6 foot southern ocean beauties and get caught inside and unfortunately only one way to find out :( but a change in technique, gear might help. Or i stick with smaller surf, nope that's not going to happen

There is always the other option of a waist leash, which most big wave SUPsters prefer.
It will flip you over, drag you headfirst, in a way that speeds you to the surface and no drag on your knees or ankle.... and sounds like none of the issues you experience with your "opposite" leg from the leashed one.
I have never had the experience you have, where the un-leashed leg, is pulled away from me in any painful way.
My leash is always on my ankle, right leg (weak knee), regular stance.
On all hard breaking OH waves, once underwater,I tuck my legs together into my stomach.....
then uncoil slowly, with resistance, as the "pull" hits me.... to avoid any "snapping jerk" as the leash reaches it's full stretch.
When I am fully extended.... I go as streamlined as my portliness allows, hands extended over my head, to put as little stress on the entire system.
I do not anchor myself, to avoid strained joints and leashes.
I have an unrelated knee weakness in my leash leg... and this seems to work, without any strain on the knee.
What I try to avoid most is a pull that will yank my ankle to the side and bend my knee sideways.... that might take me out.
I also dive under big sets... and dive deep (if water depth allows) to escape the full power of the lip.
Here's an awesome shot of my buddy GUSU, in Portugal.
He was teaching a girl to SUP surf, when they go caught by a set.
He said "Dive"
She said "What?"
"DIVE!"....
then showed her the perfect form