Could you give an example to flesh out the question?
Okay... say you have anger issues.....
does it make more sense to believe.....
1. I was born that way or
2. My dad was angry so I'm angry
Or say, you don't have an angry family - but maybe something happened in your past to make you an angry person... so you necessarily immediately go to the "let's delve into your past" thing?
Firstly, you like me are too serious for this forum, you like me expect real answers. You ask real questions and even produce real situations to model answers upon. Are 1 in 10 posters here going to discuss on the same level? No, but your efforts probably do help to organize perceptions of 9.
The past does condition us. If our parents were angry it's likely there are phylogenetic DNA which partially dictate those responses in us.
But to answer your question, no, it's probably not necessary to drag out the past. However, true appreciation if it's dysfunction is not necessarily a bad thing, but might not help self esteem which could be related.
Again, we are back to treating the unconscious directly if we are going to be efficient and effective, because the unconscious is where anger originates.
A therapist does need to know the psychological triggers to angry reactions in order to define treatment of any kind. So reliving the past is functional in that way.
But let's examine a situation where anger is after an issue and opportunity for observation exists outside of standard therapy.
Jail.
A portion of inmates have anger issues. The closed circuit TV has plenty of opportunity to observe behaviors without regressing an individual to and through moments of anger.
Patterns of response are what the therapy will be trying to intervene in. Those patterns most often have common origins in some psychological trauma, often one that was repetitive, which created a patterned response.
There is an opposite cognitive conclusion to the one chosen by the individual in the past to counter the effects upon their psyche of the trauma, as a defense, which is of their choice to select for action related to the trauma that IS under their control. In the past they selected that conclusion to act upon, repeatedly, which became a response creating the pattern.
Because we can understand each other's social responses and what might originate them, an observed angry response which is repeated, can very possibly be analyzed to derive a very general cognitive process and approximate conclusion as a basis of the response which can be treated to counter the emergence of that particular response.
The treatment would essentially be post hypnotic conditional programming. An inmate would be inducted to a quasi unconscious state, the general conditions would be described, an appropriate perceptional framework for cognitively understanding the conditions which ARE the trigger to the angry response are described in several different ways, always having the same conclusion. At that point OTHER phylogenetic DNA are invoked by reference to the individuals feelings that are preferred to the one of anger which are more functional towards eliciting responses from the others related to which in turn lead to more, other positive feelings.
Once that is reinforced from several directions positively, which is cognitively correct by average, normal appreciation of behavior as a basis for response, the individual is told they will always use that pattern of cognition to impel a more positive response BECAUSE the outcome is one where they have a more positive feeling of themselves and others after the conditions have passed.
Cognition controlling behaviors based upon instinct is quite universally understood so people will, as a matter of exhibiting personal competence immediately recognize the logic leading to positive reactions although spontaneously they may never actually use that logical result to unconsciously select an exhibited behavior.
A similar appreciation could be gained by talking to family members or coworkers that are the targets of anger expressed by an individual and a general approach to treating the unconscious developed for treating the response of anger in any individual without delving into the past.
Borderline personality disorders and PTSD can quite certainly be dealt with in this fashion, but psychology is prohibited by mores of the church assimilated by academia then covertly enforced by the state or it's secret controllers. So such therapy is not available.
We all suffer.