Ask the Rules Guy: Can you use a club with finger-grooves worn into the grip?

Ask the Rules Guy

Mr. Rules Guru: I play against a guy whose driver grip is so worn that his fingers fall into the same spot every time he holds the club. Is this illegal, since taking a sound grip is part of the challenge of golf?
— Scott Vinson, via e-mail

According to Rule 4-1b, which covers wear and alteration of equipment, a club that's worn down through normal use is A-OK for play. Now, if he had purposely altered it to help him hold the club, you'd have a complaint — hitting a shot with nonconforming equipment gets you a DQ.