Help me understand your optimism. He has started less games than Rush with a .500 record. He was so bad he couldn't win the third string job on the team he has spent his entire career. He's going to come in & master a new system & get into such a groove with the players that coaches are comfortable with him as the #2 all while only getting limited snaps because the trade occurred at end of camp\pre-season?
Dallas new offense is a lot like what Lance did in college.
I've heard from 49ers fans that were at their training camp say Lance outplayed Darnold but with the drama between front office and coaches over Lance it was causing issues.
Rush isn't good. People point to his 4-1 record last season but that was all because of the defense. The offense was putrid with Rush. I don't get the love for Rush.....I 100 percent think he can be upgraded and Lance has all the talent that Rush don't have. Lance can be a high end playmaking starter. Just needs to develop and McCarthy is known to help with QBs.
You can cut Rush right now and nobody will pick him up. They have done that before but if you cut Lance he will be picked up immediately. Heck other teams tried to trade for him, wasn't like Dallas was the only one.