In case anyone else needs to look this up, torque-plus-angle means seating the threaded fastener to a base torque, and achieving the target tension from there by further turning the fastener a specified angle. So super duper simple and something that many of us have done instinctively or from instructions, now we know there is a term for this general technique. Cf https://dannysengineportal.com/torque-specification-torque-t...
So "tighten till you hear a crack, then back a quarter turn" has merit after all?
Yes, though instead of the bolt or part cracking it's the click of the torque wrench, and you're going a quarter turn extra not back.