Surely you would get half movement if one servo stopped working? The servo with fixed position would act as the pivot point and the servo moving would swing the long arm back and forth so you would get some movement.

How often do servos stop working anyway, not very often these days. I'm guessing all the Hawks flying in Germany use the kit set up and I've seen a lot of footage of them flying.
I'd leave it alone.
I was told Skygate built Ali's model anyway so it would have the stock set up for elevator etc

Matt