Aside from psych. testing, what can a psychologist do that a lcsw can't?

They are different : Both groups of professionals have a great deal to offer people in the way of psychotherapeutic interventions. Psychologists may engage in teaching and research as well as clinical practice. LCSW's tend to focus more on clinical practice. The training for both fields is with a different focus and the amount of time in training varies. Both fields are extremely important in helping people get well.

Counseling: Both provide counseling, psychotherapy, and support. The difference is in the clinical training and experience

Psychologist: Often they can get higher positions in government work, more money, and are prioritized at universities for teaching and research. Rates of reimbursement from insurance companies are higher, as well.