I read this in Sam last chapter in AFFC. And that proves only that Alleras is Sarella (not that Sarella is Aegon!).
Sphinx are also mentioned in ACOK when Tyrion first times go to small council (delivers Tiwins message). This would S=A supporters take as proof but that doesn't mean anything. That could mean only that Cersei is trying to act like a man.
I have one theory myself which I will publish at this thread one of this days. I will give you some ACOK citations that will show you that prophecies could be used in any theory (only ACOK citations because that is only original book (written in English I have).Others are translated to Serbian
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