While burnishing the rep levers on Renner wippens, I realized that the index cut in the lever causes friction! As the key is played, that cut/groove/gouge travels forwards along the knuckle (while the knuckle rotates on the lever). The mark, if it needs to be there, belongs on the side and not the top. I looked at my Kawai action model and the mark is on the side of the ABS rep lever and NOT on the top. Good for Kawai.
Really, what a bad idea it was in the first place. I hope it gets corrected industry-wide.
While they're at it:
Taper the top portion of the dowel Let Off buttons on grands. It would be so much easier to get a tool in to adjust the jack rest screw.
Also, use square drive screws. How much easier it would be to work on vertical hammers without the flair of a slot bit screw driver. A ball-end square-drive driver operates at an angle. Plus, a screw stays on the driver as thought's locked on for installation.
------------------------------
Regards,
Jon Page
------------------------------