Dear Matthew,
Keep the putter sole just touching the tops of the grass blades and not down on the dirt. This requires you keep the height of the pivot the same throughout the stroke.
The path CAN BE straight back and straight thru but only on short strokes. Once the stroke goes back past about 8 to 10 inches, it will inevitably come inside a bit. On the thrustroke, the same is true, but you really need to make an effort to keep the putterface moving square thru the ball and beyond 5 or 6 inches before letting the path curl bacjk inside and around. I always teach that the lead elbow has to continue down the toe line parallel to the putt's startline, but after 8 inches or so it doesn't matter. If you use a "dead hands"style of putting, don't worry about the path and just make sure your contact with the ball is flush.
Your distance control sounds instinctive, and that's what I teach as the way it should be. So don't worry about the feeling of uncertainty you have. Keep doing what you are doing. The reason you have uncertainty is because the wrong part of your brain is grabbing for control like a drunk in the front passenger seat. The part that really controls the instincts for distance control does not participate in the little quiet conversation that is always going on in your head. It just knows what to do and does it. When you toss a small ball into a wastepaper basket, what "talk" goes on inside your head? None. The talking part feels weird because it is spoiled and used to running the show, but you have to ignore it. When you start to understand the true quietness of your instincts, you'll leave them alone and stop bothering them at work with the yammerings of the wrong parts of your brain.
Hope this helps.
Cheers!
Geoff Mangum
Putting Theorist and Instructor
The PuttingZone
http://puttingzone.com
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