For the time being, I'll just let the video do the talking. There are others things that I want to add to this page, but I don't have the time right now. There will be another video placed on this page after I finish editing it and uploading it to YouTube. However, the one below has all the basics. BTW, this video features the Standard stack with the "flexible fingers".

Part 2 (below) endeavors to explain why there is generally such a difference in the amount of lost motion in the three basic sections of the player mechanism (bass, tenor, and treble). It should also be noted that making this simple adjustment reduced the amount of effort (pumping) required to make the music play by one-half. And, although it is not shown in the videos, the lost motion adjustment and the let-off adjustments, in the action of the piano, were done before the stack (windchest) was put in place, to begin the regulating of the stack-to-action lost motion adjustment.