Im pretty sure it was a regular theme, defection was a major theme from the old TIE fighter game, and they DID defect during sorties in that game… however they dont use “expected losses” as the primary driver for defection, and didnt keep expected losses as a secret for the script. (Actually, maybe they did but i dont recall). … anyway, defection is a big theme, han solo is a defector of sorts, just not to a side, he just decided he could make a living elsewhere and didnt feel the empire met his values.