A neutral grip, with neither hand rotated too far to the left or the right on the handle, allows each hand to more naturally perform its correct, designated function. For the left hand, that’s “swinging” the club. The right’s job is to “push” it. To get a feel for each hand’s role, swing any club slowly using just your left hand and then with just your right.
Together, in a neutral position, your hands provide leverage for increased accuracy and power. If your hands are out of place, however, you’re giving up that leverage — and a lot of birdies.
A neutral grip may not feel comfortable at first, but stick with it. Once you see shots come off the club far and straight, you’ll see why it works so well.