Sure! If done right (right gauge wire, epoxied correctly, etc...), you could easily use one pushrod (w/ minimal weight savings I would think). As for myself, I always like redundancies. If one clevis or horn gives out, you still have the other clevis/horn on the other elevator half. Now, if the servo or main pushrod gives way, you are in deep trouble in either case. With a solid pushrod pull-pull configuration, the MagicExtra in turn gives you similar redundancies (dual pushrods, dual clevises). With a "wired" pull-pull, you would not have this redundancy that would allow you to still fly if a rudder's clevis or pushrod went out on you during a flight. Granted, wired pull-pull is lighter by all means!

One note on attaching elevator halves,... cut the joining wire (pref, 2-56 on smaller models, 4-40 on larger) such that the ends go into the elevator half at least 1 inch (the more, the merrier). Now the key,.. when you attached the control horn, try to position the horn so that the horn's screws surround the embbeded wire in the elevator halves. Basically, you want to position the horns directly over the embedded wire such the force of the controlling servo is placed upon the embedded wire rather than the thin balsa of the elevator. If using two horns (one for each elevator half), position the horns similarly.