Yes, you can find the peak performance by ear for AS, but the very process assumes you aren't starting with a problem you don't know you are fighting, such as high frictional forces or variable horizontal torque forces across the platter surface area caused by such things as the tonearm wires or out of level armboard.
Certainly, skating force is a moving target, but the bounds of variation are well studied and they aren't all that great from min to max though I do believe you could hear a difference if you applied your setting for max and then listened at the min or vice versa. Setting for average gets you in the center of the distribution curve.
We have heard a very famous tonearm designer exclaim that his tonearm sounds best without anti-skate applied, to which I say: I believe he experienced that! But I need to ask: what was his starting torque force before he applied AS? Did he know this torque force wasn't enough to have caused him to misalign the cantilever at the time of cantilever alignment? Did he know whether the arm has its own friction problems PLUS a horizontal torque problem before starting the evaluation process, either - or both - of which will keep one from ever achieving an optimal AS setting?
Of course, all of this is measurable.
