Why spend more valuable time on practice that isn't paying off? I'll be the first to tell you that practice doesn't make perfect; practice makes permanent. What a lot of my students need-and you may need as well-is a way to make your practice helpful cumulatively. This means that last month's practice helps you this month, and this month's practice will help you in the future.
It's my belief that a pendulum-type motion in the putting stroke is essential to this kind of learning. A pendulum motion means that the period, or the time it takes from beginning to end of the putting stroke, is the same whether the putt is short or long. Consider a pendulum: a mass suspended from a fixed point. If we start the pendulum swinging with a short arc, the mass will move slowly through its arc. The time it takes to travel through its arc is defined as its period.
If we start the same pendulum with a longer arc, the mass will move more rapidly through its arc, but its period will be the same. It has the same time to travel a greater distance, so it moves faster.
In relation to putting, this means that a short pendulum stroke produces a putter head that is moving slowly at impact. The result is a short putt. A longer pendulum stroke produces a putter head that is moving faster at impact, resulting in a longer putt. The length of the swing determines the length of the putt.
There will be no muscular "hit" in this motion; instead, you will swing the putter back and through with a constant tempo. A swing, rather than a hit, will lead to the consistency that is needed to learn cumulatively. In time, you will learn that for slower greens, a longer stroke is necessary to produce whatever length putt you have.
A key to making a pendulum stroke is learning to maintain your shaft/arm relationship throughout the stroke. Any wrist breakdown during the stroke changes the angle between the shaft and arm-and this means no more pendulum motion.
A final note: With any change in putter or putting style there will be a need to rework your touch, or distance control.
And remember: There is no better time than now to begin your cumulative learning.