Well there is now someone else who is thinking why McFadden.  With all the money tied up in the RB position, and a big hole in the run defense, there is another person who is asking themselves why DMAC.  Of course this particular person, has an active stake in that decision.  One more RB, means more competition,and with as much money as DMAC will make, the scrutiny will be more than it was for JR, since most people think rookie QB's shouldn't start right away.  Running backs, on the other hand should be able to come in and grasp the NFL rather quickly.

So here is the article on Michael Bush, and he states that he will work hard even with DMAC, and push him for carries.

When Michael Bush first heard the buzz, he wasn't thinking that this was just the typical business nature of the NFL. Or that it was just more potential competition. Instead, one very familiar word came to mind when Bush heard the Oakland Raiders were flirting with Arkansas running back Darren McFadden.

"I was just like `Why?' " Bush wondered.

Bush conveys the moment like a man who has been asking himself that question forever. And some days in Bush's mind, it might seem that way. Since Sept. 2006, his career has seen little more than turbulence: A broken leg against Kentucky in the opener of his senior season; a second surgery a month before the NFL draft; plummeting into the fourth round of the 2007 draft; and then a long climb back with the Raiders that ended with an unexpected deactivation in November - without logging a single carry in his rookie season.