Thank you so much for posting this technique. In the past I've included a narrow binding inside the outer binding, but did it in a separate layer of binding. This is easier, I think - why didn't I think of it?
I also just tried a (new to me anyway) method of binding, from a tute by Sharon Schamber. Use School Glue with a tiny tip on the end of the glue bottle. The glue essentially acts like pins, so you don't need a single pin. After you put a skinny line of glue on and line up the raw edges, you press with a hot dry iron to set the glue. It just needs a few seconds and the glue is dry and holds it all together. She even uses it to join the pieces of binding together, using no pins. They are sewn after glued together. Then you pop the glued seam open, press open and trim seam allowances. It might take longer than using pins, but it's so much more accurate and no struggling with the top portion of the binding moving more than the bottom layer - even if you use a walking foot. And joining the two ends of binding is a breeze! I used this method on 6 placemats a couple days ago and it worked like a charm. You can SID on the other side or do by hand. Since these were placemats and will be washed frequently, I did the last row by machine.