APT - chart only, page-573

There are some basic charting tools which would work even without the 'self-fulfilling prophesy' effect. I mean, even the very most basic 'follow the trend' would tend to work. Bubble charts would still play out even if everyone forgot about the concept, breakouts (both up and down) would still occur, etc. The more obscure and complicated, the less 'real' the effect is and the more it comes down to self-fulfilling prophesy, but even that means it does work.