My opinion is as follows:
(bear with me) Finger and coil spring (Borg and Beck style) pressure plates are generally are centrifugal in the sense that the fingers are a weight that flys outward making the pressure greater (to some extent) when RPMs are higher. If a clutch driven disk is installed correctly, and has cushion springs(wavey flat component between friction surfaces), the pressure plate tension will flatten the cushion springs to completely flat. The friction material is basically noncompressable, and so the pressure plate has no possible way to go further toward the flywheel. The portion of the engaging feel as the clutch starts to move the tractor, and that point where the pedal pressure drops off as it comes out, is the cushion springs doing their cushoning. The fingers should try to apply more pressure as the RPM increases, but there is (again no where to go. If they move at all it would be less than 50 thousandths.
There should be no where near as much change as you are indicating.If the disk was installed backwards, and the torsion spring set (coil springs spaced around the center of the hub of the driven disk) was against the flywheel, the pressure plate would be put in a bind that would have the pressure plate pushing on it before it touches the flywheel. This would cup the disk, and allow it to drag when fully depressed, and not release all the way when the pedal was out (It has happened many times to experienced mechanics). The angular contact of the PP on the friction material makes it seen like it has very thick cushion springs, and would allow the fingers to actually do as yours are doing. The only other element that might affect this is a bad flywheel resurface job, with wrong technique, and wrong numbers. My best guess is to pull it apart again and see what is between the friction surfaces. JimN
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