We have a Desktop based WinForms application. Application performs some very complex logic in database and is bound to take long time. By long time i mean it will take anything from 1 min to 20 min for processing. In this time user can't do anything and has to watch the progress bar. Now, We have communicated client that calculations are such that. it can't go faster. He acknowledges that yes its optimized but it feels slow for end user.
I wanted some suggestions on how do we handle long running operations on UI which may create illusion of application being a very responsive and fast.
My idea was that right now user is observing very static progress bar. If I put some text or some notification where I have reached in processing it may have better impact on usability.