This is madness. San Francisco won because of Frank Gore. Without Frank Gore, they might not have won 2 games. I guarantee they would have been the worst team in the NFL again. Their run-blocking is not good, their pass blocking is only better than the Raiders, and their defense was one of the league's worst.
But with a great RB - perhaps the league's best - they got to 7-9. An amazing accomplishment considering the talent they ACTUALLY have.
That's what a great RB can do for your team. Only a great QB is a more important asset. Having a great RB doesn't make you one-dimensional, and having Johnson wouldn't make anyone one-dimensional either, as 2005's Chiefs can attest. Having a RB like Johnson, Tomlinson, Gore or Jackson is worth EVERY penny, if your team can afford it. Kansas City has bungled their cap, and can't. If we had a reasonable shot at Johnson, and we thought he could remain healthy for a few more years, there's no way you don't take a shot at that. Our team would instantly be super-bowl favorites. Because the ONLY thing holding this offense back is a strong, consistent run game.