Hum-cancelling in the split positions of a humbucker type pickup?
 

I was wondering if it was possible to obtain hum-cancelling in the split positions of a humbucker by doing an "alembic" and wiring the grounds wires directly to the ground rather than to the neck-coil/humbucking/bridge-coil switch? (or however they do it, I think this is how, may be wrong)

Um ... what?

Umm... Yeah ... You can do that ... Just make sure that when you do you have a decent backup bass, because what you just described could render your bass silent

Maybe the idea behind the first post was to have a coil split that affects both pickups at once, so if the coils are split the whole combination remains humcanceling. That is possible.

The Alembic Series I electronics use two single coils and a middle dummy coil. The signals from the coils are added together actively.

The Series II use stacked humbuckers.

Grounds on pickups would always be going to ground. The hot wires go to a switch.

If you are talking about switching coils in a humbucker, yes, that would be parallel wiring.