I finally got a round tuit and opened up the cushion to look at the polyfill. Yup, packed down. I've just spent an hour tearing wads into fluff. Fluff is nice, leftover fiber dust is not nice. I still have 3/4 of the filling to go.
There MUST be a better way to do this. Wool carding cards? (Not that I have any, or any money to buy any, or any money to buy new polyfill. I think I'm doomed to another few hours of fluffing.) A home carding machine?
I remember reading, years ago, that after each winter, Chinese housewives would unpick the family's padded coats and send the cotton batting out to a shop that cleaned and refluffed the padding. The coats would then be resewn. They would be clean and fluffy, ready for the next winter.
Wish I had a shop like that nearby.