FWIW - Andy Dalton played his freshman and sophomore NFL seasons in a Gruden offense and his numbers were:

Rookie:
3400 yd - 20TDs - 13 INT -  9-7 record

Sophomore year:
3670 yds - 27 TDs - 16 INT  - 10-6 record

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Also - the only 2019 rookies that seem eligible for slumps would be Taylor, Allen, and Minshew and frankly none of those guys seem poised for such a downturn. (other rookies had injuries and/or low snap counts) 

  * I think Minshew progresses but has a few tough games against the better defenses that force him to throw from the pocket. I think he eclipses 4300 yds passing and throws 25+ TDs and takes the fumbles down to 6 or 7 total. 

 * I think Taylor takes a moderate step forward but gets humbled by a handful of speed rushers sprinkled throughout the year. 

*  I think Allen has a very productive year getting after QBs and shows some solid versatility against the run.

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There is some evidence out there  that shows QBs who perform well as rookies often take a downturn in year two. 

I'm remaining optimistic about Minshew not falling into that category, but we can't know until it happens.

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