[Geoff]

This idea is pretty good:

"Take a piece of electrical tape 5 feet in length and stick it to the floor in your house somewhere the wife will not move it. Everyday for a month set up to the tape with your putter and walk your eyes down it (toward the hole) and back to the putter face. IT MUST TAKE AT LEAST THIRTY SECONDS. Now read all your practice putts for the next month. After thirty days you will know if you are linear or non linear."

But you don't need tape -- just use a line on your floor, such as a tile floor or the plank of a wooden floor. The phrase "walk your eyes down it" really reveals something about what is happening in this exercise. There are two different movement systems potentially used to "walk" the eyes down the line -- the eye muscles and the neck muscles. The eye muscles (six extraocular muscles per eye) control the "gaze," which is the direction the eeballs are aimed out of the face and skull. The neck mucles aim the head on the trunk. If you hold your head still faing the floor / ball at address and try to "walk" your eyes down the 5-foot line with eye muscles altering only your gaze, you will not be doing what golfers need to do in putting. If you partially turn your head with your neck while also changing the direction of your eyes with eye muscles to "walk" the eyes along the line, you will experience a messy process that generates very questionable sense of the line. However, if you fix your gazeteady direction and then turn only your head to "slide" or "run" the end of your fixed gaze / line of sight in a straight line down the 5-foot line, you will experience clarity of the line visually and also clarity of sense of direction to the target by virtue of the neck nerves.

To see how to really sharpen this process up, make a narrow tube with your hand and hold it to your dominant eye (close the other eye) and -- looking thru the tube of your hand like a telescope or spyglass -- aim the gaze straight out of the face perpendicularly to the plane of the face. (This would be like a pirate sanding with good posture at the helm scanning the far horizon of the ocean for a booty ship.) Setup square to your line on the floor, aim your face and "tube" at the floor so te gaze remains aimed straight out of the face, and then turn the neck to "slide" or "run" the gaze down the line. If you turn your head on the axis from center of neck out top of head so the axis rotates but does not arc backwards or otherwise, the line will stay inside the narrow tube all the way as the head turns down the line.