With the TA predictive (indicative) argument, I often read from many people that you don't need to be able to predict, it's how you manage the trade. I understand what they mean, because you can't know how the trade will go, it may go 10 pips, it may go 100. You shouldn't limit profits arbitrarily as LV pointed out earlier, and management is key. But the management of the trade is just another form of prediction. You take the trade, it's not working out after so many minutes or hours, so you exit, or you move stops or whatever. You've exited, perhaps, not because you knew with certainty what would happen, but because it wasn't doing what you expected or wanted, and you've predicted the probabilities are not in your favour any more. But this is just prediction - based on TA - of likelihood, rather than a precise outcome.
So if TA is not predictive, then the dilemma becomes, how is it that it can suddenly become predictive when in a trade, but not before? How can it be, that "It's what happens next that counts (limiting loss, taking adequate profit, finding momentum etc", when these are just decisions, each of which can clearly be (and usually is) based on price movement (TA)?