The ink and pen speed look good, so if David says it's an authentic 'rushed' signature, I believe him. The opinions of JSA and PSA are, as always, irrelevant...to me, anyway.
I would like to see a guide to common 'rushed signatures'. There was a Gehrig David posted a while back that was very intriguing, and I would assume that most Gehrig rushed signatures would have a similar look. This is the first Ruth of that type that I've seen - it's interesting that the 'a' is open, which is sometimes a forger tell, but apparently also an indicator of Ruth being in a hurry. Another type of signature that it would be good to have guidance on, are the ones that were signed at an angle - I've seen some autograph book pages where it was very obvious that all were real, but all were also signed from a strange position.
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