PERFECT LINEThe Take Away
There're two big issues here. Face alignment is about what you should do with the putter face as it goes back and stroke direction is about the optimum path for the putter to take.
Face alignment is a debate between allowing the face to open and keeping it square. If the putter face opens on the take away you need to return to square at precisely the right moment to propel the ball down the line and that's not easy under any circumstances.
Alternatively, if you're square on the take away, square at impact and square on the follow through you don't have to rely on perfect timing at all, in fact some of your bad putts will even find the bottom of the hole. It's no contest.
The most consistent take away is along the ball-target line and square, anything else and you will ultimately come undone under pressure.
Less consistent is a take away that's square-to-square on an out-to-in or an in-to-out path because it will put a degree of sidespin on the ball.
The most inconsistent take away would be an open face on an out-to-in or in-to-out path - the ball could literally go anywhere. It's not something we recommend.
Another issue is putter head elevation. A putter that gets above the ball on the take away will descend on the ball on the through stroke and cause it to jump and loose power. So imagine taking the putter back under a pane of glass resting on the ball and you can't go wrong.
Once you have an efficient stroke you need to know how to control the power. When it comes to teaching distance control there have been many teachers and many theories but we don't believe in intangibles, instead we have a method of distance control that relies on synchronization - not touch or feel.