I currently have a MM and a P pickup wired passively VVT (250K pots) with the MM wired to a switch giving series/single/parallel. They sound good individually witha lot of snap from the MM and plenty of body from the P pickup. But there isn't a lot of value blending the 2 together at the moment, and I guess that is because of things I don't really understand about pot loading, imedance and direct current resistance. Ideally I'd like to be able to sneak a bit of the P pickup in to add body t