Q: Our centipede lawn is nearly gone. Would it be beneficial to let fallen leaves stay on the ground throughout the winter for potential nutrients and/or protection?
A: Allowing your leaves to remain will probably kill any grass that is present. A damp layer of decomposing leaves will allow fungi to attack the grass underneath. Fallen leaves contain very few nutrients. It would take a very thick layer to add any appreciable organic matter to your soil. I think your best course is to shred the leaves with a mower and then rake up any piles of “shreddings” so the grass isn’t covered. You can assess matters in May and decide whether to reseed then.