When the USGA announced in 2013 that anchored putting would become illegal (effective January 1 of this year), club designers got to work. Their mission: Give players who anchor a legal option. Today, advancements have made counterbalanced putters a popular choice. Compared with conventional flatsticks, these putters feature a heavier grip (due to a weighted insert in the butt end of the handle) and head (up to 50 extra grams). And they tend to feature shafts that run up to five inches longer than standard; when a player takes his normal grip, a good portion of the handle (and the additional grip weight) is above the hands. Combined, these modifications lead to an MOI (moment of inertia, i.e., stability) comparable to that of anchored putters.
How does counterbalancing steady a shaky stroke? According to Austie Rollinson, chief designer at Odyssey Golf, adding weight to the ends of the club makes the bigger muscles—rather than the "twitchy" ones in the wrists and hands—move the putter, resulting in a smoother stroke and improved roll. "In our tests with the Odyssey line of counterbalanced Tank mallets, about 60 percent of players immediately improved their strokes," Rollinson says.
The Odyssey data suggests that a wide range of golfers will benefit from one of these designs—but not everyone. "Counterbalanced models work best for players who swing the putter straight back and through," Rollinson says. "But if your stroke path traces a significant arc, you'll probably have a hard time squaring up a counterbalanced putter."