Every insert putter is trying to solve the same problem. A soft material feels pleasant and damps unwanted vibration, but it also eats energy, so the ball comes off slower. A firm material gives you speed and then sounds like tapping a stone on short putts. Most manufacturers simply pick a side and move on.
Ai-DUAL uses a two-layer insert. The upper, softer layer is about 1.2 mm thick and handles feel and sound. Beneath it sits a firmer layer that acts as a springboard at impact. Cleverly, the soft layer is not a uniform thickness — it is thinnest in the centre and grows towards heel and toe.
On SAM PuttLab we ran three players (handicaps of 4, 12 and 19) through sets of thirty five-metre putts. Ball-speed spread on off-centre strikes dropped 11 to 14 per cent against a conventional White Hot insert. That sounds modest, but over ten metres it is the difference between finishing half a metre from the hole and a metre and a half.
The more interesting number came from distance control. Our 19-handicapper had a 2.8 metre spread of finishing positions on twelve-metre putts with the old insert, and 2.1 metres with Ai-DUAL. Long putts are what create three-putts, so that extra quarter has real value on a card.
What Ai-DUAL will not do is teach you to aim. If you set the face two degrees open, every putt beyond three metres misses regardless of what the face is made of. Aiming is a function of eye position over the ball and putter length, not of face technology.
Practically speaking: if your putter is more than five years old and you putt reasonably, moving to Ai-DUAL is probably worth half a shot a round. If you putt badly, spend the money on a lesson and a PuttLab session first. A club of the wrong length and lie will not help you whatever is bonded into the face.
We stock Ai-DUAL in the One shape (blade with toe hang) and Seven (face-balanced mallet). There is a putting strip in the shop on Galvaniho — three metres of artificial green running about 10 on the stimp. Bring your old putter; a side-by-side comparison tells you more than any magazine test.
