I assume they see themselves shifting to a passing offense (more a passing offense compared to where they were before, anyway) as Lynch starts to decline. They'll still build the offense around running, because that's what Pete does, but Russell is going to have to shoulder more of the load and become the engine of the offense.
That said, they haven't really been asking him to block much:
Also, the biggest reason the team has struggled so far:
Disappointing, especially with Pete devoting an entire day of practice each week to turnovers.