Additional weight in the butt of the club alters the balance point, decreases the swing weight, and increases the overall static weight.
When you add weight to the butt end of the club, you shift the balance point of the club towards your hands and raise the overall static weight of the club. You also decrease the swing weight, so the head will feel lighter.
It’s a control issue – lighter clubs have less feel, while heavier clubs offer a force to push against.
Having properly balanced clubs allows golfers to swing better and make better contact.
The Science – extra mass is placed in the grip end of the club to counter a heavier head. This weighting technique boosts the club’s overall moment of inertia (MOI), so that it swings and feels more stable throughout the stroke.
While most golfers will benefit from weight placed into the butt end of their grips, not every golfer will benefit from counterbalancing every club, this is the reason that SwitchGrips was specifically designed to come with a >2g (non-weight).