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I must admit, until you brought it up, Matthew, I wouldn't have been thinking about it, but now, I can't "unsee it" as you say. That is, in regards to the second one on down.
I'd have never thought to ask, in the dental care sign, "Where is the right knee of the patient?"
But as for the first one, I don't see any "getting ready to spank" posture, but rather I see a kind of square dance or running-down-the-beach, hand-in-hand posture.
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