The 'feel' of the mechanical rotary comes from the 12 position switch. If you were to attach one of these, but not actually activate it. You could then use the method where you use a belt or rubber bands to hold tension against the shaft and connect the other ends to the mouse encoder. This would give you the feel of a mechanical, but the accuracy of the optical. It would in essence be like having both of them active, but you wouldn't need druin's board in this case.