That's a reasonable adjustment from never to rarely...
Almost all Freshman RBs, even 5 stars struggle to be fully functional, and fully capable...by that I mean they limit the offense based on their learning curve, and while they may have elite physical tools, the mental part of the game usually causes them to be less effective... The elusiveness, vision, and execution you saw in Cierre and Theo over the last couple years, especially at the second level is not common for a freshman. Not going to say GB won't make an impact...going to say odds are way against him being your "guy" regardless of his physical gifts.
...BK seems pretty adept at creating an environment for success when he is forced to use young guys...but seeing the guys he has, and his comfort with veterans, I think he'll not need to use GB, nor be all that inclined to force it.
I am not ready to say we don't have a BCS level RB. Our D-line may well be the best in the country, so looking at the spring and deciding we don't have BCS caliber backs seems premature.
So...I'll go out on a limb and just go ahead and name one...we got time to argue it ...

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Carlisle seems a complete back. He may not make an entire season, but he has break away speed and elusiveness in tight spaces...He'll have a very good O-line, and other players on the field which will force defenses to be honest. His story will depend on health and how they use him. It seems to me if you line him up at slot, with cam or GAIII at tail...that's a tall order for a defense...so while his production may not be "BCS" leading man production, his presence in that spot forces more mismatches and more options for EG...If Carlisle is the primary tail, he'll be very productive if healthy, and he'll be 1K+ rusher. I think Carlisle is an elite BCS caliber back right now (ok in another 6 weeks or so ...

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