The primary metric I believe is important in evaluating the viability is TA is the number of people that "believe TA works." To the extent that other investors

The primary metric I believe is important in evaluating the viability is TA is the number of people that "believe TA works." To the extent that other investors trade based on mystical figures on a chart, the price behavior may start to match investor movement and become somewhat of a self-fulfilling prophecy, at least until more meaningful fundamentals start to stabilize the behavior.