I doubt you could put anything to equal the straining arms of a frightened pilot - which seemingly fail to do the job. Those wheels were springing back on the cable tension.
No, the power has to go in the other end. Just one small motor (via clutches) is capable of driving the jackscrew. If I was filling a bin with sketches of ideas, one of them would be a second electric motor capable of at least assisting the hand cranking.
On the 1-11 I spent years with a larger wheel between finger and thumb manually trimming the T tail while hardly moving the pole. It was utterly perfect in its follower motor smoothness. - that's if you allow for the 3 degree hysteresis to give the mach trimmer some breathing space.