Quote from kjkent1:
The mathematical theorems that underlie all trendline formula, state as axiomatic, that none of the data points used as input for the trendline, can exist beyond the endpoints of the trendline.
Therefore, attempting to use a trendline to predict future direction of a security is impossible, because the science behind that trendline prohibits such predictions.
That was the long version of saying that I agree with you...trendlines are total BS.
LOL!
Markets are high dimensional systems - that is, expressed by many variables - but still contain a great deal of structure. I believe that trends can help reducing the dimensionality of markets to make decisions. Ultimately, traders should look for models for which the equity line lies on a well identified tracjectory in their searching landscape. To make a story short trends can certainly be used with great result but with a non "Technical Analysis" flavor.