Let ne get this straight. a clean stall. Pulling gently back, as we get to 1.1 Vs or so the cowls tend to fly the airplane nose up so the stick pull force lightens instead of getting slowly heavier.
That doesn't suit pedantic test pilots, they want a smoothly increasing pull force all the way to the break. So we put a ghost in the circuit to drive the stabilizer L.E. nose-up to fly the airplane nose down so we have to pull that little bit harder. Fine.
Now we are hand flying clean at 250 knots, a dozy AoA probe drives the stab L.E. nose up. Back stick rqd to hold attitude. Re-trim. Release switch. The airplane is now in trim. A few seconds later it happens again. I don't see it getting any more than minimum displacement from the in-trim position. Also. the bacon slicer, it must have moved while the ghost was trimming because the stab trim screw-jack drives it full time. And v.v.
Should be flyable. Even without operating the stab trim cut-outs. However, airplanes functioning irrationally can be very disconcerting. I can see a crew nonplussed by such an apparently inexplicable and sinister turn of events getting, in the end, confused.
I think Boeing the FAA and EASA are going to have to talk pretty fast to get out of it. A single failure like that shouldn't cause this much grief.
Btw, the only 737 pilots who by now aren't on to the existence and function of the stab trim cut-outs must have been asleep or dead for the last six months... so why aren't we back in the air?