I think all jokes are explainable why they are funny to be honest. I find it odd when people say that explaining a joke removes the funny part. Sure, it can in some cases, but I think it's just a generic thing to say rather than what actually is the case. Sometimes a joke is so clever, that you don't get it at first, but then someone explains it and you appreciate how clever the joke was, which is still a positive feeling and in addition can make you laugh retroactively.