Clutch not fully disengaging - why?

[Xcellr8]

Update - having replaced the pinched clutch line and the slave cylinder, there was no difference in shifting (Or should I say lack of shifting.)

Worn out fingers on the pressure plate is moving up the list of possibilities, but I can't reconcile how the car was driven upto this point. Isn't it true that the fingers would have worn out gradually? Which I would think would cause the shifting to become more and more difficult gradually. The condition of the shifting today is so poor that a driver would never have gotten to this point. The car is not drivable in traffic. To downshift you have to shut the motor off, put it into the gear you want, then restart the car. Tony Stewart might be able to do it save gas the last few laps of NASCAR event, but not everyday. I think what happened to this clutch/transmission happened all at once and that does not sound like gradual wear.

Correct me if you have a theory.

Thanks,
Joe
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