I've never done it, but I can see why drops are hard to un-braze; there might be 1 inch of dropout plus brass inside the stays. Cutting the dropout will help, but I doubt air-mapp has enough heat. Plus keeping the dropout intact would help to find a suitable replacement, in order to preserve the geometry of the bike. And don't pull on the dropout while the stay is hot, it can easily break apparently. Some bikes do have pins (you should see it if you remove the paint and clean the metal), and even some had a tack weld!

Your best bet would be to setup some sort of forge... firebricks on a piece of angle iron?