That's the main reason I'd ever use it. The advantage is that it rearranges the wood at a molecular level, and the result is much less strain on the wood when bent. Basically, you can bend wood further with ammonia than with heat. Heat/steam-bent wood will try to recover its initial shape when reheated (eg during heat treatment). Not with ammonia.
But we are rarely confronted with situations that steam or dry heat cannot handle and which only ammonia could.
