Through 2 games, Arizona QB Khalil Tate has a total of 15 carries for 22 yards. Last season, he rushed for 1,411 yards. I bet he's missing Rod Smith...
Kevin Sumlin is doing to Tate exactly what Zook and Mike Schultz did to Juice Williams, with similar results.
And really, both Juice and Tate bear some responsibility as well, both wanted to transition to pro-style passing.
You want either delusion about the suitability of their game to the pros (Eric Crouch), or acceptance that their pro future is in a different position (Braxton Miller). When you get caught in the middle area, you can really have disappointing upperclassman results from promising young QB's.
The results at least seem better when you evolve slowly within the same system (Tim Tebow, Lamar Jackson) rather than going "new offense, I'm a pro-style passer now".