The biography of Blondie has a little bit of detail on this. He first tried this rig on a canoe, then a 12ft Firefly dinghy, then decided it was OK to try scaling up to put onto Jester, built in 1953. This photo would have been taken during trials in the Solent in 1954 or 1955, in which the windward performance was found lacking, due to being only ¾ of the area of the bermudan Folkboat, and also the stresses in hard weather were thought rather high, even for Solent sailing. An idea ahead of its time? With the benefit of later technology as used on the Freedom and Nonesuch rigs, Jester would perhaps have been fit to cross the Atlantic with it, Blondie wouldn't have started looking at the alternative of the JR for easy handling, and we'd all now be members of the Lapwing Association. Maybe.