In some real deal applications like connecting rods on engines you can stick your head into. Techs will measure when a bolt has reached a correct torque spec when the bolt has stretched to certain dimension measured with a micrometer.
Torque is also very misleading depending on material. Steel bolts stretch in what feels very linear. Stainless steel bolts, when those are tightened up it's like hitting a wall going from loose to tight.
Click sticks (torque wrenches) also have something to say. Where you hold your hand on the wrench will affect the torque value. Usually there is a line on the handle showing you exactly where your hand should be placed and pulling from.