I stand corrected.Les still plays fretless regularly. He put the Rainbow Bass down for a little bit during the Brown Album and Antipop because he was being pigeoned holed for all of his tapping and the like. It has since been brought out during most, if not all, of his side projects. He also uses his 4 string piccolo fretless also, though somewhat less often, but it's still in regular rotation. I haven't known him to play his jazz since the Brown Album era.
-ryan-