I praise any admiral who is patient enough to wait for their heavily damaged battleships and carriers to heal normally. Their patience is that of a saint.
Patience or the fact that all their resources are now gone by spamming use of a battleship, aircraft carrier fleet so they have to wait it out to replenish.
If you know you aren't gonna play for the next day(or are going to sleep) it's not that much of a stretch to let your battleships or carriers heal normally.
20 hours to heal Nagato? Well considering I'll be gone all day tomorrow, go and take that bath Nagato XD