Diverse, I see you mentioned something about prehearing in your post, and perhaps you have always been in fortunate situations where you ALWAYS know the song somebody is going to sing, and had a chance to prepare it in advance. Unfortunately for me, this is not usually the case. Somebody will start singing, and for that matter even on songs that I know, if they are in a key that I never have played the song in does that mean I should just sit there and look stupid? Well I personally prefer to be an intelligent musician, so a lot of my playing involves what you have nicely termed pre hearing. That is what ear training is!!! It is about developing your ear to know what is coming next, before the singer gets to it. For me, ear training has never been about making things up out of the blue. it has been about making things up based on the musical knowledge I have gained by playing in other situations. That is developing your ear. You never stop listening, you never stop practicing, and you never stop learning why the things work the way they do. Making your ear stronger is about total package musicianship. I think I can compare it to learning a new language, such as Swahili. If someone is talking Swahili to you, sure you can learn by trial and error. I may take you years to do it, but it can be done. You can listen to what the other person is saying, and even copy it, but would you really know what you are saying? More importantly would you really be able to communicate what you wanted to say to them? It may help to learn the language first, and then trying talking, and listening to the language. Even when babies are learning to talk, they learn by association, and hearing, and they they learn how to form their own sentences and express their own thoughts more accurately, the older they get and the more they learn. Music is no different. Would we all really want to stay at the baby stage where we are copying off of what everybody else is doing only? Or would we rather get to the point where we can express to others our own thoughts, and then people are copying from us?