Band conflict is most often seen as a bad thing. It demonstrates that there are competing views and differences of opinion. This in and of itself is not the problem. The way conflict is handled is where the problem lies.
Often there is a predictable course that rehearsals take when there is ongoing conflict in a band. It begins with an unspoken agreement to avoid topics that cause tension. Since collaboration is so crucial, the subject inevitably gets voiced. Tension in the room rises and words are exchanged that have been said many times before. The rehashing with no constructive resolution is so frustrating that one or more members storm out and the rehearsal ends.
For example, say a band of four members has two that have co-written a song. The jamming is going well and then comes to a decision of whether to include a drum solo. Good arguments are put forth for both cases, but everyone begins to feel the clash of personalities. Neither artist can “lose” the debate because there is more at stake than the decision itself. For each artist, there are issues of who “wins” that have roots in each of their individual histories. There are also models of how these scenarios have played out in each of their lives (with parents, siblings, girlfriends/boyfriends, etc.). When the conflict ends by simply separating, or setting the song aside to work on a different one, little is gained.
However, a lot can be gained by staying in the conflict and changing up the predictable pattern. Maybe one of the two can decide to defer to the other’s opinion, when normally his style is a “fight to the death.” Then, at a later more peaceful time, there could be a conversation about experiences of the past and how they creep into conflicts in the band. Another change might be to pause the rehearsal to talk about the tension itself. Everyone could be asked to talk about how the fights are affecting their feelings about being in the band. This likely will lead some members to refer to difficult past experiences (whether or not they choose to speak in specifics).
These ideas of handling conflict in new ways take a certain amount of courage and kindness and are not easy to enact. But taking the less predictable path leads to fresh discovery interpersonally and artistically. And, knowing your fellow band members better will also help you play together better!