For sailors using an autohelm (joystick or sip ‘n’ puff steering), positioning the driver forward of the traveler removes the seat from the path of the actuator-driven tiller, and has the additional benefit of moving the weight of the driver and seat closer to the center of the boat. In this setup, the main trimmer works behind the traveler, switching the mainsheet cleat to the back of the barney post. And a shortened tiller offers more room for the main trimmer.
The seat slides easily on two curved tracks, and the driver can be “tacked” from side to side by the main trimmer, using a line that runs behind the seat, and is locked down in a cam cleat on either side of the seat base. The photo above shows the seat as originally built by Gene Hinkel for Y-Knot Sailing. The quadriplegic sailor using this seat subsequently removed the footrest, and replaced the black plastic molded seat with an aluminum race car seat frame. This sailor also prefers to sit centered in the boat and not move from side to side.
In the photo above, Dave Whalen and Dan Kennedy of Y-Knot Sailing take the seat out for a test run. Note the two metal bars that connect the back of the seat platform to the traveler. You can also see the line (white with blue flecks) that loops behind the seat, with a cam cleat on either side that allows for easy positioning of the seat. In this photo, seat has been moved to leeward for light air. The red line running across the boat between the spinnaker blocks provided a grab line as additional hand/arm support for the driver.