It looks like I had some of the steps a bit out line, but then one question still remains. If Ginny, Ron, Hermoinie and everyone in the wizarding world except Harry knew that it was bad to say Voldemort, wouldn't they all have known it was equally wrong to mention Tom Riddle, at least to the point that when Ginny first met him in the book, something should have clicked?

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A Nerd can figure out how long it will take the original Enterprise traveling at warp 6.5 to travel from Regulus to Antares.
A Geek will think he can use that to pick up a girl in a bar.
A Dork knows he can't pick up the girl with it, but will hang around for hours anyway, just in case she asks.
She might. You never know.