Yes, actually. I learn almost all the music I know by listening, but there are certain things that are difficult to distinguish just by listening, particularly parts played by doubled or sometimes tripled instruments. Sometimes I will listen to a piece and attempt to transcribe it by ear, but this does result in the problem of not being able to tell if I have listened and transcribed correctly since I cannot see what the actual score looks like, nor hear an orchestra play my version to see if they match up.
Long story short, there's no way to tell for sure if I am actually getting the whole picture just by listening.