Those are challenging but relevant questions/comments. One of the DSM-IV-TR diagnostic criteria for BPD is "inappropriate, intense anger or difficulty controlling anger (e.g., frequent displays of temper, constant anger, recurrent physical fights)." Not all BPD patients manifest these symptoms. But many do. And why? Because of the core of repressed, dissociated rage resulting from severe narcissistic injury during childhood. Often this rage is directed toward the self, in the form of self-injury, suicidality, etc. So, based on my own thirty-five years of clinical experience providing psychotherapy to hundreds of patients, including many with BPD or BPD traits, I believe this core rage must be consciously addressed, acknowledged and redirected in such patients. Of course, much of this depends on the context, strength of the therapeutic alliance, degree of ego strength, etc. Clinical judgment is key. And it is a gradual rather than abrupt process. One which must be contained, constantly monitored, and facilitated in a highly structured frame, therapeutic container or temenos. But I have always found that this acceptance, by both therapist and patient, of the long-standing anger or rage, and an understanding of where it comes from and how it has been manifesting itself in destructive and self-defeating ways in the patients life, behavior and relationships,is absolutely essential to successful psychotherapy. By which I do not mean mere symptom management.