Is Brandon Jacobs 'expendable' or not?

The 49ers have generally managed to avoid too many injuries thus far this season, although obviously that took a sizable turn the past couple weeks with Alex Smith's concussion. One area where they have been fortunate thus far is at running back. Frank Gore is having a strong year, thanks in part to Kendall Hunter spelling him enough to keep Gore fresh.

The 49ers signed Brandon Jacobs this past March and based on his early preseason appearances, it looked like he was working his way into a short yardage role. He suffered a knee injury during the preseason however, and even as he has returned to practice, he has been inactive in all but one game.

There has been a lot of chatter about whether the 49ers should release Jacobs given some of the grumblings we've heard and there general lack of use for him. There are times I find myself wondering if that will eventually happen, but it all comes back to the "insurance" role he would appear to fill.

If Frank Gore were to suffer any kind of injury, it seems like Hunter and Jacobs would then work in some sort of split of carries. Obviously we'd prefer it never come to that, but if that is the case, it seems like the 49ers might as well hang on to Jacobs as long as they need to this year.

For those that are fine unloading Jacobs, would you be fine with 49ers boosting Anthony Dixon's role in the event of a running back injury? It seems like that would be the result if Jacobs were released, so it begs the question of how comfortable you are with Dixon as insurance over Jacobs as insurance.