Thats the way SF operated under Shanahan and McDaniel... Well... Thats the way the whole NFL kind of operates when it comes to RBs... Mostly... And lets face it, its not like SF were this great running team, they were pretty much middle of the pack when it comes to YPC or even big plays out of it... They were simply good enough to be able to run very often -> which in turn made opponents have to go single high -> which in turn created more space for a guy like Jimmy to be able to finish 2nd in YPA... Yeah I know... Unbe****inglievable.