I'm no golfer but why would a golf club maker think a more elastic metal would be a positive thing?
Golfer seem to live in perpetual obsessive search of The Magic Club that will hit balls further, more accurately and give them a hole in one every nine holes.
That aside, the theory went that because this metal rebounds so well in collisions, (which is demonstrated in the above video of a ball of the metal bouncing off a hard surface) it wouldn’t put energy into temporary deformation of the club face and instead put more energy into the ball.
I will always subscribe to the assessment that golf is a way to ruin an otherwise perfectly nice walk.