Following the disaster of Missionary Ridge in November of 1863, the Confederate Army of Tennessee went into winter quarters at Dalton in north Georgia. Braxton Bragg resigned in disgrace, with William Hardee, the senior corps commander, taking temporary command. IOTL, Davis appointed Joseph Johnston to command the army, but before he did so, he offered to appoint Hardee to the command.
Hardee turned Davis down. He claimed that the post should go to Johnston, who outranked him. He also seemed to believe that corps command was the level of responsibility that he felt most comfortable with. Furthermore, he was about to get married, and had he taken command he would not have been able to take the time off for the wedding and honeymoon.
So, what if Davis had simply overruled Hardee and outright ordered him to take command, or what if Hardee had decided to accept the President's offer?
Hardee was a good corps commander, though not brilliant. His few weeks in command of the Army of Tennessee before Johnston arrived seemed to demonstrate solid administrative competence. And his time in independent command in Savannah and South Carolina in the face of Sherman's advance in late 64/early 65 seemed to demonstrate some skill on his part; the evacuation of Savannah was certainly very well handled. On the other hand, I see no real evidence that Hardee was much of a strategic thinker.
So, what do we think would have happened if Hardee had been appointed?