Lee's order has been criticized because it left too much discretion to Ewell. Historians such as McPherson have speculated on how the more aggressive Stonewall Jackson would have acted on this order if he had lived to command this wing of Lee's army, and how differently the second day of battle would have proceeded with Confederate possession of Culp's Hill or Cemetery Hill. Discretionary orders were customary for General Lee because Jackson and James Longstreet, his other principal subordinate, usually reacted to them very well and could use their initiative to respond to conditions and achieve the desired results. Ewell's critics have noted that this failure of action on his part, whether justified or not, in all likelihood cost the Confederates the battle. Other historians have noted that Lee, as the overall commanding general who issued discretionary orders to Ewell and then continued the battle for another two days, bears the final responsibility for the Confederate defeat at Gettysburg.