[Ajedi32]

You don't really need your feet to swim. In my personal experience when swimming most propulsion comes from my hands, not my feet. Once you can tread water with just your arms you'll have plenty of time to figure out how to swim with your feet without having to worry about sinking.

[pmarreck]

I've found the same (I think most of my propulsion is from my hands) but I always assumed I was doing it less efficiently (but didn't care)