there's study out that directly ties size of sled to the erection quality achievable by the operator. I'll pull it up for you guys. its filled in the office of true stuff next to the truck study. all in all the results are very telling. it also goes on to explain the popularity of tiller designs as it taps in and reminds the driver what a firm cock feels like. all in all an interesting read. definitely helps explain the lack of manners by some tiller jockeys. they are in the final stages of mourning for their penis.