I would say no.
If you remember the 2002 season, Lamar Smith was the starter and Fox worked him Shanahan style. He was getting 20+ carries a game. He wasn't very good from an NFL standpoint, but he was racking up multi TD games for fantasy.
I can't remember if Lamar Smith got hurt or benched, but I remember not being able to use him during the 2nd half of the fantasy season.
Also remember that 2002 was DeShaun Foster's rookie year. Many people were salivating over him because he had broken off some big run in the preseason... but Foster ending up getting hurt before the season started (sign of things to come).
So in 2003 they decided to go out and get Stephen Davis, who they worked Shanahan style when he was healthy. Davis had multiple 20+ carry games and even some 30 carry games. The only thing that stopped Davis from getting a big workload was health.
In 2004, the entire RB roster got hurt and Nick Goings ended up with the starter's job. Once again, when healthy, Fox's RBs got hefty workloads with up to 30 carries in a game.
In 2005, Davis was ineffective and Foster had been pegged as a Tatum Bell type... good situational runner but can't handle a full workload.
Anyway... Fox has had some "RBBC", but not by design... The guys he's had have either been not that great or injured often. If you know who the starter is in Carolina, you know he'll get a big workload as long as he's healthy. Kind of a mini-Denver situation.