Yeah it's possible to achieve excellent results on demo, however when you want to repeat this success on live you will likely fail because trading conditions on real account often wipes out exchange. It concerns the most trading systems based on speed and which rely on very low spreads.
Exactly and it works because I am very confident about my approach and strategies. I wouldn't be going live even with the micro account had I not done a thorough market research, which is what I suggest to people, that there is no hurry to go live. First get all the knowledge, do their due diligence and then get started with a micro account.
Demo accounts work great when you have to practically test what you have read and learned about while studying the forex market. As no real money is involved, it helps build confidence and prepares for live market conditions.