On flat greens with no break, hitting the ding line is essential to getting the putt in the hole. Even with forgiveness of the putter, if you are out more than the ding line thickness you will miss the putt from 10 feet most times.
With freehand putting you learn to compensate for the break on greens by allowing the ding line to move right or left of the centre line to allow for the break. How much you allow the ding line to move past centre comes with practice, a great amount of it but it can be done.
Allowing the ding line to move with freehand means that the putt will not go as far as it would if you hit the putt on the centre ding line with aim putting but with practice you can get the distances more or less bang on allowing the putt to drop.
Using the triangle is the way to go on the greens, no doubt, but I have sank 140 foot eagles using the freehand method so it can't all be luck, or maybe it is LOL.
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