One major reason Personal Ensign may not have been considered for the Classic was that Phipps had a two horse entry of Seeking the Gold, who finished second, and Personal Flag in the race.
Not saying otherwise she would have run but I'm into full disclosure.
Plus it seems it's never really been Shug's MO to run fillies against the boys. I can't think of any (besides PE in the Whitney), but you might remember more than me.
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please use generalizations and non-truths when arguing your side, thank you