No, it can't be used, because all Humans show improved muscular separations as their bodyfat drops; however, some show more than others, making the measurement of bodyfat levels using this technique foolish. Sorry.
SUCKMYMUSCLE
what technique do you suggest judges use then. if not cuts since they also are variable, and striations too. wait a minute so is HARDNESS. so based on your logic only things that are linear and constant can be used to measure conditioning.
id like to hear your suggestion as too how the judges can do this. or even a phenomenon in bodybuilding that adheres to your logic.
the reason some show more others is based on many factors that are impossible to know. size, shape,water, fat etc if you lack sep, thats your problem, you got the shitty hand in the genetics department.
what is this linear variable. since all non-linear variables are useless.