Who came up with this primary crap to start with? I think the system probably worked better when presidential nominees were decided in smoke-filled rooms. At least the people who were smoking there were knowledgeable enough to know who the best candidate for their party would be. Would they ever have come out with something like Trump?
I'm not sure they did, but they usually picked some inoffensive glad-hander that the majority of the internal factions could live with. I'm not sure anyone was like "damn Chester A. Arthur is really well-versed on policy."