The way I do it is to kneel forward with the crossbar or tiller extension under my foot. This holds it still, and you can steer a little bit. When dropping, I often leave the tiller completely and allow the (cleated) main to start heading the boat up. Needs a bit of care in stronger winds <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

One simple system I've seen used on an FX-one is a bit of velcro around the tiller extension, and a bit on each end of the back beam, allowing the tiller to be held in a fixed position.

I don't know of anyone on an F16 using a self-centering system, and in the UK at least, most of us singlehand regularly.

Paul