Dear Clyde,
Such "visual" aids to observing pendular timing are already available. Jane Crafter many years ago looped a piece of string around her finger, at the bottom of which was a fishing weight, and then took up her grip on the putter and made strokes so the weight would swing in time with the golfer's stroke movement. Harold Swash's "whippy tempomaster" is essentially the same thing. Both of these are superior to the abstract and mechanical tic-toc of a metronome, because each is specifically "geared" to the individual golfer and that golfer alone in moving on earth.
If you have something additional in mind along these same principles, let's hear it, by all means.
Cheers!
Geoff Mangum
Putting Coach and Theorist
Geoff Mangum's
PuttingZone
PuttingZone Clinics
Flatstick Forum
PuttingZone Channel on YouTube
PuttingZone Picasweb Image Gallery
Golf's most advanced and comprehensive putting instruction -- you're either in the PuttingZone, or not.
Over 2.5 million visits -- 200,000 monthly from 50+ countries -- and growing strong.