I have a theory that there a benefit to using a line contact stylus on a worn record. My rationale is as follows:-
A record that has been played on a old player, with a heavy arm is most likely to have used a spherical stylus. This will have worn a pattern in the groove walls, where the spherical stylus contacts the groove walls. A line contact stylus has a wide contact line with the groove wall, not just a point, and so will bridge the wear pattern and play the unworn groove above and below the wear.
I have no proof that this hypothesis is sensible, but it seems logical, albeit there are many reasons why a record may have been worn by more than one stylus, or may have extreme damage. For a record that hasn't been excessively abused, just played with a heavy spherical stylus, there may be merit in my suggestion.
Certainly, I have lots of old records bought in charity shops and the like that are over 50 years old, yet play well with my line contact cartridges.
Any views?
S