The last statement you made there is exactly the point. When we measure sentiment based on price action, there is reasoning to that. Price action is one step removed from Sentiment. Anything else comes after that. People often say sell the news. That's because news is old as soon as it's written, which creates chasing. The news attempts to explain the price movement. Sentiment actually drives the price movement. Now whether you want to believe that is a measurable factor is completely up to you.
I didn't used to believe it, but as I learned more about it, and I watched the news and press releases and government mandates come in over and over to justify the measurement of sentiment....AFTER the fact....I couldn't ignore it.
Sentiment drives the price, thus price movement is the FIRST indicator, and everything else is trying to fill in the blanks. That doesn't mean TA is meant to nail every number every time...although it often does. It just means that you are working with the element most closely related to the actual price movement. Fewer variables to botch the forecast with....no emotion attached, no personal connection to sway what the price movement tells you.
How it is measured can be considered quite esoteric....but what matters to me is what works. I don't need to assign a reason why it works if it works, although there is a reason that I believe to be true. As humans, it is very difficult to release the need for explanation.
The TA we perform here is based on two techniques. And we do believe that News or Events Shall Arrive to Justify the Forecast, and NEVER the other way around.
The success of this blog is not due to someone selling dreams to people or a great amount of lucky projections. It is due to Haejin being very very experienced (through trying many techniques and having tonnages of failure), and then developing an approach to analysis that is successfully projecting price pathways with a percentage that is above 90%. I know of no other method that has ever produced better results.
As a side note....just because I apply a very specific technique certainly does not reflect on my ability to comprehend or to be aware of any degree of freedom of understanding. It is an intentional move based on positive results.