I'm curious to learn why poles seem to be preferred over blades/rails in pickup construction - why is that? What do poles get you in terms of pickup tonal quality that you don't with blades? Is it simply a cost thing? In the area of string bending, I would think that if a blade picks up vibrations all the along the course of that blade, wouldn't that be a better than poles that lose the signal when the strings are bent away from them? Any insight?