I think it interrupts the point. Hearing the sound of the racket is a gage on how fast the ball will be retuning. I was at Wimbledon when they made Monica S stop grunting. Pitty what happened to her. What do you think...
I'm not a big fan on grunting. I think it should be allowed but only up to a certain level, level in decibels. I think the ump should have a decibel reader and check from time to time. Teh WTA and ATP could run some tests to see at what point it masks the sound of the racquet hitting the ball and set the level there.