I cringe when ammonia spray touches my earthworms but other than that, 10% ammonia doesn't seem to affect anything else besides slugs.

Removing flowers is debatable. Some believe flowering signals the hosta to make more roots. Others disbud so more energy goes back into the plant. Still others allow hosta to flower but not set seeds. Mary Chastain doesn't allow any lst year seedlings to bud.

You're dealing with people's habits, beliefs, and myths. Take whatever you read with a grain of salt, experiment on your own, add some common sense and do whatever works for you.