Runaway trim has been on Boeing's emergency checklist since the dinosaurs. So, the implication is that the MCAS fault has similar symptoms to that classic fault. But nothing in the facts gleaned from the Lion Air accident has indicated that indeed the symptoms the pilots would experience are the same.
But here's the rub. Pilots have to recognize the problem in order to react appropriately. If they're fighting what feels like a bucking bronco, that's counterintuitive when normal control wheel inputs don't respond. If I pull back on the control wheel in any airplane, the nose should rise and not fall toward the ground. So, while this nightmare is occurring, most likely the crew is being inundated with a menu of error messages and warnings, some of them audible; having multiple distractions is an understatement. And don't forget, in both circumstances the airplanes were relatively close to the ground, shortly after takeoff.
Once again, even as an expert, I am speculating. Although the circumstances of these two crashes appear very similar, other explanations cannot be discounted at this point in the investigation. We need to hold our breath just a little bit longer. The FAA and Boeing are under tremendous pressure to find answers quickly.
As for the question so many of you are probably asking: Would I fly on a 737 MAX? Yes, in the United States -- but I can't deny my comfort level would be low.