Seriously people, use the fucking fan. It clears away odors and covers up the sounds of your dropping a deuce. If you want to stew in your shit smell and revel in the music of your magical poop plops, do so in the comfort of your own home. If you’re a guest and the bathroom has a fan, turn it on. We don’t want to share.
How do you know when to stop wiping?
Blind people smell the paper. Since I learned this, I do it too. Olfactory is a better standard than visual for this.