I'm not sure I'd quite go along with a blanket claim that the stabilizer is resisting what the elevator is trying to do. You can't really treat the two surfaces as separate entities. What you have is a total unit that alters both camber and angle of attack at the same time versus a full moving stabilator that can only change its angle of attack.

For small deflections the stabilator will have a lower drag than the separate surfaces. However there's going to be some point at which the camber aids the lift required to direct the tail of the aircraft where a separate stabilizer and elevator will have less drag than the all moving stabilator. At some other point the drags to lift may cross again but since it's related to so many variables you'd have to analyse specific situations.

This is totally aside from structural stiffness and strength issues of course. Strictly lift and lift to drag required to move the tail around.