Happy feet, bad footwork & mechanics, poor reads, general lack of command of the offense, etc. We got killed by penalties inside the redzone last year. If that happens to him, ok it's not on him. Yates was 20/34 for 200 yds last year with a line completely whiffing on blocking assignments. That's a guy many fans on here don't consider to be a P5 QB, who had much fewer practice reps because he was the 2nd or 4rd option at QB. Surely Sims can muster better than 70% completion percentage and another 50-100 yds passing with all his talent plus the advantage of having starter reps with the offense all August, with a competent QB coach and vastly better OC & lineman who've been in the system 3 years plus taking snaps behind very high caliber transfers.