Subjective...Yes, as per Drdel's points. Though the Aimpoint line shown on PGA Tour shows an accurate line.
Unenforceable...No. That's part of what 'The Committee' (as per Rule 33) is for - Rule 34-3 applies. Whether they get it right or not.
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In the absence of a referee, any dispute or doubtful point on the Rules must be referred to the Committee, whose decision is final.
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