My point is that a border line under-rotation is not clean. It is not not-clean.That's why we have judges, to rule in border line cases.
The unclear edge call is a more pristine example, I think. Unclear means unclear. Unclear situations arise in every sport with rules. Did the wide receiver get his big toe down a split second before his knee hit the turf, or a hundredth of a secod after, Did he have full control of the ball at that instant, or on;y 80% control?
Two baketball players collide -- is a a blocking foul on the defense of a charging foul on the offense?
The fLutz call has a particularly tangled history. Back in the day, almost every woman and a whole lot of men "failed to present a clear outside edge" on their triple Lutz. Those who did, it is not apparent from the judges' scores whether they received any scoring benefit or not.
Fans as well as the ISU Technical Committee went round and round on the question, if you slip over to the inside edge at the last moment, is the jump to be scored as a "flawed Lutz" or as a "flip" -- taking the definition of the jump from the take-poff edge alone. If the technical panel gives a "!" I suppose that is them saying, "Don't ask me, I haven't got the foggiest."
After years of hand-wringing and fights between the "pursts" and the "even more pure purists" as to what a Lutz jump is, they (we) kind of settled down to something like the following compromise:
The most important factor in a Lutz jump is the counter-rotation. (This is also the reason that a pure Lutz is rarely under-rotated,-- compared with a Salchow, for instance, which is almost always under-rotated.) If the skater slips over onto the flat or onto the inside edge, this releases the counter-rotation prematurely and the result is a flawed jump. In a proper Lutz the skater rides that outside edge and, if anything, deepens it at the moment of take-off.
In a questionable case, when the tech specialist says"!," how much GoE should be taken off? That's up to the judges. It is the reponsibility of the judges to offer their judgement on that question.
(A hat-tip to GS poster gkelly for explaining that to me.

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