The truth may well be somewhere in the middle Edward and Stan. Taking Richmond wasn't a guarantee they'd stop Lee. Going against an entrenced force wasn't a pleasant thought. In the end, it was the starving, the lack of supplies and the fatigue that caused Lee to decide it was time. He could not bring himself to ask more from those who gave him as much as they were able. I believe he understood that Grant would be less inclined to take out his vengence on the Confederate troops than he was on just getting the whole ordeal over. It also brings up the question: what if it had been Sherman making the decisions at Appomattox? Somehow I think we're glad we don't have the answer to that one.