Nah...he volunteered to move to FB so that Rozier could go full time. Or they asked him to make the switch. Can't remember now which it was...either way, it always seemed to me that he was the forgotten guy back then.
Roger did play some FB on the "I' formation. He had a nagging ankle sprain that hampered him virtually his entire senior year. Doug Wilkening played FB most of the time in 1982.
Back then, Nebraska was also experimenting with a split back formation trying to get both Craig & Rozier in the same backfield, called the "weak set".
While there was more of a running threat with Craig & Rozier in the same backfield, Osborne also said he didn't want to "take a great I-back and turn him into an average fullback ."