Ranger82, Fallon was not "better" but Fallon was the Commander of CENTCOM and as such, he has the authority to make decisions or recommendations about the Central Command region. Petraeus is in charge of the Multi-national force in Iraq.
It's a chain of command or authority issue. It is simply not Gen. Petraeus' authority to determine the movement of forces around CENTCOM.
If Ranger means you were an Army Ranger, surely you understand that. When one appoints a person to be in the chain of command you don't skip echelon to find out what another general suggests no matter how able that general. Perhaps McCain wants to make Petraeus CENTCOM commander.
If Gen. Fallon, or any CENTCOM commander does not have the necessary qualifications to make recommendations about the deployment of troops in his or her command, then they shouldn't have been placed in that position to begin with. If Fallon wasn't qualified then that speaks to Bush's incompetence.