The item in question had an incorrect premise. The premise is that "Baltar was able to extrapolate the location of the Lion's Head Nebula ***just from reading the sacred scriptures***". But Baltar used more than that. For example, in this episode Gaeta says that Baltar also used: "map of the constellations found on Kobol". Therefore the conclusion is incorrect and in fact no one without the map could have conducted the same research.
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