And don't forget, if your elevator is physically jammed, the trim tab will work as a small elevator - but in reverse sense
This depends on the type of trim. It's certainly true for an anti-servo, as used on the PA28. But with other types of trim system, such as the VI tailplane used on the PA18, it will work in the correct sense.
How often have you heard of the elevator becoming jammed? If it did happen at low level, I don't think you'd stand a chance. And at altitude, you'd have time to try various things, and you'd work out which sense the trim wheel works in by trial and error.
(This subject seemed to form a disproportionately large portion of the ATPL syllabus. It's interesting, and helps understand how each of the trim systems works, but doesn't seem to have very much practical use as far as I could tell.)
FFF
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