the magnet sensor (what your crank sensor is) creates a magnetic field around itself, and when the crank (or cam) gets in range, it sets off a pulse to the ECU that occurs every rotation of the crank or cam shafts.
i don't really see stress causing a new one to fail, would almost seem like it's shorting the new one out somehow. when i had issue with crank sensor, my car didn't shut off, the MIL came on and i replaced both the cam and crank sensors and she's been running fine (never took her in for recall)
i'd actually check my wires between the sensor and the ECU to make sure there are no loose connections, what other sensors gave you problems? what codes are you throwing besides crank sensor? you might be looking at a faulty wiring harness. (check to make sure no rodents have chewed any wires or anything like that, also check for heat damage)