Just machine washed the ones from my '84 for the first time, warm water
and ordinary detergent.  Much brighter now, the faded areas show up much
clearer!  No shrinkage or harm done, but I would safety pin on a piece
of cloth with the location of each side curtain on it next time.  They
are all the same size but the tie back strap attachment points are
different, and the holes from these attachment points remain after
washing.

Well worth it to get rid of that gritty feel!

Stuart