give it a try Danno. The pole will not be under straight compression like a column would. With one end of the pole attached to the dolphin striker and the other end being pulled down by your weight, the pole will want to bend at the center. I tried this with a closet pole to test the system and the pole nearly snapped on the first try. Then I tried it with an aluminum mast from an Optimist, and it worked (except that the pole needed to be longer). I finally came across an old H16 boom, and that is what I have now, although it is huge, heavy and cumbersome to have attached under the tramp. When I have a moment, I will get a 1.75" diameter aluminum tube x about 8 feet in length and use this. I don't think a tiller extension will work. I think it will bend in the middle, especially if it is a telescoping one.
The drag chute that Bill spoke about seems like a great and simple idea, although i'm sure that in light winds it is comletely useless.