Following a thunderstorm, with torrential rain in the Alps, I found another use for a spare heavy sweater tucked in the bottom of my rucksack. All other clothes were completely soaked an we were bivvying in a ruined high alpine barn. The roof was collapsed so there were plenty of wood roofing tiles to get a fire going to dry out our gear. I pulled on the spare sweater as an emergency pair of trousers, though the neck was leaving the family jewels a bit exposed to the rough seating. A spare lace came in handy to close up the gap.
Some weeks later, when my mother discovered some extra washing, she could not make out why I should thread the neck of a coarse weave sweater with bootlace using a blanket stitch.