I do this naturally, but I don't make a point of it. It just happens. I just took a month to learn 17 Smiths tunes for a tribute band. Those of you who know the Smiths know Andy Rourke's playing is not text book, but certainly in the "high degree of difficulty" column, especially if one had never heard or studied the Smiths. His position shifts are quick, repetitive and in time. To do many of his "tricks", I had to employ and practice the OP's technique a lot. Especially switching from pinky to index to increase my speed and reach up the neck. When I caught myself doin it over the years, I'd practice it, tryin to get the finger switch and next phrase as seemless as possible. I never go in to a tune with the idea I must employ the technique. But my hands seem to naturally draw upon it when necessary. With a bit of intent practice I understood what my hands were attempting to do, and I let em go to work. And? Don't tell anyone, but I also rake strings with my plucking hand. Supposedly a bad technique, but one I see pros use all the time. Your hands will, in general, do naturally what you need to get a job done. Once we learn what our hands are doing, it's up to us to practice it til it becomes invisible. I can employ the technique anytime, now. But I let my hands tell me when it's necessary.