My grandfather could soak a piece of wood in ammonia and when it came out of the soak he would shake it, it literally looked as limber as a rope. I have been using the ammonia method for tight bends in wood for a long time when I was fresh out of school my first job was as a carpenter doing finish work I made round windows and arched windows in a church they would soak that wood for says in straight water once I told them about using ammonia it would be ready to bend in 24 hours.
never has when I've used heat I was using an adjustable heat iron for shrinking up covering on Planes. Haven't tried it since I switched to a curling iron haven't needed to bend anything that wouldn't work with just water and heat. I only use ammonia for scrolling just about any other bend you wont need it and you will find most of the time you wont need heat when using Ammonia.