SilverWook said:

I could have sworn Palpatine mentioned midis during the opera scene in ROTS?

"Darth Plagueis was a Dark Lord of the Sith, so powerful and so wise he could use the Force to influence the midi-chlorians to create life ..."

That's what he says. Not that interesting if you don't make Palpatine tell Anakin that he used this power to create him! It was the "I am your father" of the prequels. There are earlier drafts of this scene where this side of things was very obvious. But even if Lucas used the early draft, He could have just tell the same thing by saying the Sith used the Force to create life. No need for Midiclhorians, unless maybe the goal is showing the dark side 'scientificaly' using the Force against its more spiritual nature. Maybe...