All therapy is "black magic" in the sense that no-one quite understands exactly how it works. CBT gets props because it's one of the few therapies that has a manual and can actually be studied scientifically.
I'm sorry but I prefer to speak with a therapist who doesn't have to consult a manual for every response he/she makes. Therapy is ultimately a human relationship, and just as messy and unpredictable as any other relationship - and subject to all the contingencies thereofe.
Just because something cannot be studied scientifically does not mean it is not effective. Evidence for the limited long term effectiveness (high relapse rates, ect) of shallow and manualized interventions like CBT is growing by the day. Compare that with more messy therapies that dig deeper (like psychodynamic) whose outcomes actually improve the longer the subjects are tracked.
The vast majority of the effectiveness of therapy is due to hope (placebo effect) and the relationship. Focusing on the "technique" is distracting and leads to a view of therapy as something that is done to you, as opposed to something that is done with you. Lasting change comes from taking personal responsibility, not from having special "scientific" techniques done to you.
That para-professionals with 2 weeks of training have outcomes as good or sometimes better than those with Ph.d's in clinical psychology is all one needs to know when deciding whether or not to categorize psychotherapy as a science.