He will have to wait to prove it, however, after Birmingham's weather forced the abandonment of the first Test as a draw, denying him the chance to make a winning start as England captain.
England, 170 for 7 in their second innings after 45 overs of positive, attacking cricket on Sunday evening, had declared overnight, challenging South Africa to score 290 on the last day, which disappointingly saw not a single ball.
"I felt we were in the box seat," Stewart said. "It was our intention to score as many runs as we could on Sunday and then give ourselves all day to bowl South Africa out. We felt we had played daring cricket to go for our shots as we did, but sometimes you have to be prepared to risk defeat in order to win.
"I thought we had a good lead. It was not impossible for us to take 10 wickets in a day and, to be honest, I did not think they would be able to score 290.
"We'll never know now how it would have turned out but having played well for four days we can go forward with confidence. If we continue in this form, there is no reason why we cannot be smiling at the end of the fifth Test."
Stewart's predecessor, Michael Atherton, was named Man of the Match after his first-innings century and earned special praise from the new incumbent.
"He's been under a lot of pressure and showed his character here. Good players have bad patches and great players come out of them. I'd put him in the latter category.
"I don't know whether it was not having the responsibility as captain that made it possible but I certainly never saw him play a reverse sweep as captain."
Stewart's counterpart, Hansie Cronje, conceded that the sub- standard performance by his bowling spearhead had been the difference between the sides, although his criticism of Allan Donald and Shaun Pollock was low key.
"They were short of a good rhythm," he said, "but they are allowed a bad day or two."
England's bold agenda, page 26