Thanks for the pic. Yep, that would be nice for two reasons (versus a universal claw mount derailleur): 1) Derailleur is not hanging free when wheel is off (claw mount came with screw and nut but does not line up to anything on the Dahon frame, it's designed to fit the end of a long horizontal-slotted dropout), and 2) Could mount any derailleur; Fortunately the claw-mount Shimano Tourney TX has worked amazingly well, despite its low price.