It's for the same reason we don't get a king out of check by announcing this is a silly game and tossing the board out the window.
To the plausibility of Shinzon's career: admittedly, going from discarded slave to battlestar commander is an unlikely path. On the other hand, if we didn't have the example of history to go by, would we call Napoleon Bonaparte's career at all plausible?
To the plausibility of Shinzon's career: admittedly, going from discarded slave to battlestar commander is an unlikely path. On the other hand, if we didn't have the example of history to go by, would we call Napoleon Bonaparte's career at all plausible?