My last on-the-road tube patch was nearly a decade ago when I helped out a fellow rider. Local guy, he had just gone out for a nice Saturday leisure ride and flatted. He didn't have a spare tube, patch kit, tools or even pump with him.I happened on the spot in all my touring glory, kitchen sink and whatnot.
If it happens to me, I just change the tube and patch later in a more convenient place. I carry a couple of spare tubes and a traditional patch kit.
--J