Quarterback Shuffle is worst than expected
"Sure, luck means a lot in football. Not having a good quarterback is bad luck". This was said by Don Shula who was the head coach of the '72 Dolphins and coached Hall of Fame quarterback Dan Marino. Throughout the whole Bears franchise, they only won 1 Superbowl, which was won by 85' Bears with their effective defensive unit, but also good offense with Walter Payton, Willie Gault, and their Pro Bowl quarterback Jim McMahon. Unfortunately, after the 85' Bears, the franchise could no longer extend their success. They last made a Super Bowl appearance in Super Bowl XLI against Future Hall of Famer Peyton Manning and the Colts, but lost (29-17) because of bad quarterback-play by Rex Grossman (20/28, 1 TD, 2 INT, 165 yards, 68 QBR)
Now, the Chicago Bears are gambling on two QBs Mike Glennon and Mitchell Trubisky. Glennon will be the 2017 starting quarterback for the Chicago Bears while Trubisky is developing and learning the playbook. Well now, the Chicago Bears have a bigger problem. Mike Glennon isn't capable of being the starter for the Chicago Bears. Because of his lack of experience in Tampa Bay and not being able to start since 2014. During the preseason, Glennon looked bad as a starter. He looked nervous and keep staring down at one receiver, which helps the opposing defense to make interceptions or plays on the ball. When Trubisky played he is great despite playing against 3rd string defenses. Mike Glennon is still the starter after his two bad games, but he isn't good and now you have a young quarterback for the future, but he still needs to develop if he wants to be effective.
It's best to prepare Trubisky by giving him 1st team reps and putting him in the game. It helps gives him a better understanding of how NFL defenses work, but also helps him evolves his game as a franchise quarterback. If the Offensive line can protect Trubisky, then there is really no reason to not play the kid. The skillset is there, but Trubisky needs to learn the playbook by the game of the 2017 season. It's best if it happens like this because Glennon will only be a backup in this league.