Fair point. Let me rephrase my point of view a little: you haven't made the users truely productive unless the tools are able to provide responsive and accurate

Fair point. Let me rephrase my point of view a little: you haven't made the users truely productive unless the tools are able to provide responsive and accurate interactive feedback. Anything that causes feedback to be non-immediate makes it harder for the user to dial in the exact results they want. They have to spend more time and give up when they have reached an inferior result that meets basic quality standards. Smooth and direct interaction makes them go the extra mile while enjoying the process.