The thing is that markets have several simultaneous trends. One cannot trade successfully without being aware of the full picture. In your example a trader would have to know where this top occurred in relation to the rest of the chart. Trading based on reliable somewhat repetitive behavior will put you well over the 50% line. On a single trade I know I am more likely to win than lose, but I can't put a number on it. In your example we know a top has been made but we don't know if it's the top. Therefore I would say the chance of a wining trade is much less than 50%. Also, don't put your stop on the high. There were sellers there and they could still be there. Last point your target is arbitrary. You need a target that has a logic to it.