Coach Miles is bringing the QB's along with a bit of foresight considered. Miles starting Jefferson has been his motto so far this season and he's certainly enjoyed what most LSU fans consider moderate success at the position. Lee, given his opportunities, has made the most of his snaps, and has been getting the passing game going with a few mistakes, understandably outweighted by a pair of game winning drives.
6 games into the season, no one would have scripted where we find the Tigers today and certainly how they got there. Lucky they call him, and that my have some merit to it, but he's no magician. Miles is working with what the Tigers realistically have at the QB position. With only 2 feasible starting QB's on the roster, his discretion lends that it's pretty important that these guys rotate at this point. Both QB'swill have experience as needed, this is the SEC, and quality depth is at a premium with how these guys play.
It would be an easy choice for me, an LSU fan-start Lee, but these shoes would be hard to fill for any coach in Miles position. Starting sets the tone, finishing brings it home!