I only pin a short space when hand sewing the binding on the back - just a couple of pins to fold the binding over and hold it in place. As I get to that pin (I only use two pins usually when doing the binding) I move it along to the other side of the other pin and just keep moving a pin over to the other side as I get to it when stitching. Sounds like Greek probably - hope you understand what I'm try to say. This works well for me and keeps the binding in place where I'm working.