Well one thing I think about with figure critiques on shapes is that it seems to me that everyone has a set of ideals they have in mind (around the same lines of what you all are talking about).  That in itself can also be idealize though I do highly agree that being close to a project does blur your focus.  I think it happens most of the time, even to folks who are very insightful.

But someone can say (just picking something random) that this figure's legs look all wrong.  And other guy or gal says well I've seen legs like that or says "I have" legs like that!  Sometimes I see critiques and think well... my elbows or toes or whatever look that way... Am I a mutant now?  Or then someone brings up an art book reference, which in itself is going to be idealized.  I have seen a lot of folks who have what I feel are big heads or rather small heads or eyes that hang down lower than where someone else's eyes do.

That doesn't mean that clearly alien looking humans should be justified as ideal, but I feel some variance in structure is okay.

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