I believe the spoilerons help kill lift by providing some down force to counter the lift of the airfoil. This downforce is behind the CG of the plane, so I believe it should give you some pitch up... almost like elevons would with up elevator. I had a plane with the ailerons up a little too high (equivalent of a little spoiler mixed in), and when it was trimmed out, the elevator was down quite a bit for level flight. Turns out the plane was also a little too tail heavy, so that would cause some down elevator to be required too...