I have to say that I wouldn't say 90% of my calls are correct for 2 reasons: it would be taken as bragging and it would anger a lot of traders on ET.
But it all depends on your approach.
I decided that I wanted to master the Dow and I wanted a very reliable system. I then decided I didn't want to use chart indicators .. for all the reasons to do with their flaws and actual applicability in live trading.
So I just did my own research, backtesting and then actual trade testing .. a long hard and frustrating but absorbing journey.
I've got my own proven system .. and so now I've got the Holy Grail I sought. All I can say is it can be done but it might be more than once you would want to give up along the way.
As well it is true too that you have to take anyone at his word when he/she posts his/her opinion, experience or results. I don't find that a problem. Most people don't post deceitfully.. and if any do .. well, it aint gonna spoil my breakfast.