Outcome studies are gaining legitimacy. Outcome studies are more appropriate to the clinical setting where the work in actually taking place. The proper measure of a behavioral technique is an outcome measure. Blindness can be assured by having the assessments done in blinded fashion, the training being done unblinded. Controlled studies are done mainly to control for the placebo effect, which is not relevant for behavioral techniques, where what has been called the placebo effect is intrinsically part of the process, and not experimentally separable.
Clinicians are right to think that any such effort is a tedious waste of time.