hardhat,
I have wondered and have came to the same conclusion before, but now I’m not sure. First let me say, I have terrible knees too. I have had 5 surgeries, no lateral cartridge on one knee, partially removed on the other, both have loose ligaments, one with arthritis, and the list goes one. The last two orthopedics I have had say that the eventually I will have to have a knee replacement. Oh such fun! Will if Bill Graham, a db member, who I look upto, can set the American static record at age 64 with a bum hip and dive 40- 50 meters with an artificial hip at age 65, than I should be okay too!
Friday I will start a serious of Synivc injections, which I get every 1 to 2 years. The injections and leg muscle is about all that holds my worst knees together. In fact the worst thing for my knees is the flu, because when I can’t work out my legs my knees get bad.
The both legs on one fin sounds good, especially since that is why some snow skiers have gone to skiboards. But in looking at good mono fin technique verses good bi-fin technique, I would say monofinners bend their knees more. They use more hamstrings and quads than bi-finners, which means more force on the knees. Also a mono-fin has a much larger surface area than two bi-fins so this could mean more force to the knees as well.
So personally I’m staying with soft bi-fins for now.
:wave don