WORLDDIVER,
I know a lot of divers are happy with their split fins, which is in line with the truth of the matter, all fins work. But, I agree with you on the split fins as they are made today. The concept is great but the way they are being manufactured defeats the purpose.
In the marketing materials they picture the split blades curved like a Force Fin to generate lift, but in reality, the water is escaping through the center. That makes them easy to kick, but you lose power, which is why you had trouble towing your friend. You also lose propulsion when the blades travel through their neutral flat position, then you have to use your leg muscles to drag them back up through the water. Basically, a flat blade with a split is acting as a paddle with a sieve.
I told my wife, when I saw the first pair made - the year after we introduced our Foil Force Fin - that they were going to ruin the split fin market with their flat design. And, I was right. They caused the throw back to the dark ages of diving with Jet Fins.... :cool2: