Nah mate, droop is where the suspension uncompresses and keeps the inner wheel in contact with the road under hard cornering. I think the latest Apex coilovers have a droop spring built in. Under normal driving it does nothing, being a softer spring, its fully compressed but if you hoon it round a corner, where normally you might cock a leg (wheel) , the droop spring pushes the wheel down so it remains in contact with the road increasing your grip and traction.
I don't think preload has anything to do with it.