The scale is useful, for sure. But it's only a descriptor to indicate pull force. Just as we describe a person as tall or short - we are overlaying a subjective description over a value that is objectively measurable - in that case, in feet and inches. Both tests have their uses, and people choose to use one or the other method depending on the occasion.
The point I am raising is that knife pull weight has never been, is not, and never will be a subjective test. We can apply a subjective description to it, but if the test is lacking or difficult to apply, it's not because the knife pull weight itself is subjective, and cannot be quantified with accuracy.
Just some basic stuff from a quick google search:
What are forces?
A force can be a
push or a
pull. For example, when you push open a door you have to apply a force to the door. You also have to apply a force to pull open a drawer.
You cannot see a force but often you can see what it does. Forces can change the speed of something, the direction it is moving in or its shape. For example, an elastic band gets longer if you pull it.
Measuring forces
A force meter is used to measure forces.
Forces can be measured using a
force meter. Force meters contain a spring connected to a metal hook. The spring stretches when a force is applied to the hook. The bigger the force applied, the longer the spring stretches and the bigger the reading.
The unit of force is called the
newton, and it has the symbol
N.