In my opinion this s a very good post (for whatever my opinion is worth ... which is exactly nothing).
There is no doubt that Rettig showed well. He read progressions, he move in the pocket, he made 9 excellent throws (the near interception and a too long sideline pass targeting Agudosi were the 2 exceptions), he showed reasonable mobility on 2 scrambles.
But Laviano also did well. He did not get a chance to run through progressions because Caroo made an amazing catch and run for 55 yards on his 1st (and under-thrown) pass, and then Caroo was so wide open anyone on this board might have been able to complete the pass to him (no defender within 15 yards of him, seemingly) - and then ran it in for 56 yards. His other 2 passes (and completions) were designed screens - 1 to James and the bubble screen to Caroo ... the last of which also went for a TD. But he DID complete all 4 of those passes. And there is also no doubt the staff had Laviano play at a totally different tempo than they had Rettig play at: several no huddle situations, for one. And I agree the offense looked a little crisper with Laviano in ... though he DID have the benefit of playing against a surely more worn down NSU defense, and having Caroo in the game. Do not underestimate the difference just having Caroo in the game makes.
It did look to me, by feel only, that Laviano maybe had a slightly better command of the playbook and offense than did Rettig. But that Rettig uses more of the field and spreads the ball around better ... maybe. A push and pull.