Black should have played 44 e5 to try to restrict White's king.
A typical line of play where Black plays an early d5 is 1.
The tentative Black plays the first move in the center of the board.
We almost assume that blacks have always played the game.
Blacks, however, play only a minuscule part in the growth.
"It was very unusual at that time to see three blacks and two whites playing together on one side."
Black should have played this line, however, because he still wins after 48...Ka7 49.
But by the time organized baseball let blacks play, Suttles was too old.
The situation seemed to improve in the 1970's, when as many as 10 blacks were playing on the tour at one time.
However, Black can also play 4 Qd5 5 d4 Nc6.