1. A dramatic template for devising theatre pieces based on a triangular relationship of three archetypes: oppressor, oppressed and liberator (as in villain, victim and hero).
This relationship can be expressed in three scenes: Oppression, Passion/Compassion and Combat.
2. A naïve, exaggerated, grotesque universe where extremes of good and evil do battle, and nightmares are made of the musicality of everything.
Imagine the world as a child sees it: populated by giant monsters, i.e. adults twice its height. Melodrama presents a simplistic, black and white morality, with easily recognisable portrayals of good and evil. Characters don't learn from experience; they are as good or as evil at the end of the play as they were at the beginning. Melodrama appeals to an audience's emotions, not their intellect. A character in a more sophisticated style of theatre would be complex and evolving throughout the play, and contain aspects of all three melodrama archetypes.
3. An opportunity for actors to explore the limits of their expressive powers while maintaining a core of sincerity.
Melodrama work can function as a springboard for expressionistic acting. The actor interprets the psychology of a situation as a kind of music with which to dance. Not just with the body, but also the voice. For example Opera: My feelings are so strong that I have to sing them, nothing else is sufficient. And what would be an acting style just below the passion of Opera? Perhaps Grotowski, Odin Teatret? Melodramatic acting requires passion; a kind of madness is needed to support the style, to lift it out of the quotidian, to become a celebration of human emotion.
The melodramatic actor is a "multi-media metaphor machine" communicating on multiple channels, not afraid of theatricality!
Certainly there is a lot of suspicion surrounding Melodrama. Is it not an exercise in bad taste? Well no, not necessarily, for there is both good and bad Melodrama. But don't worry too much about good taste. Exercises in "good taste" only stifle and kill art. Clichés need to be regenerated, not avoided. Good Melodrama succeeds when the actor avoids parody, which is a parasitic activity, sucking its own blood. The audience might well laugh at good Melodrama, but only because of the grotesque intensity of the situation, not because the actor is commenting or looking down at their own work from a position of superiority. Hence the importance of what I call the "Twin Peaks" approach: just as the situation has become so extreme that your acting is about to cross over into parody, tighten it up, defend your character, support the style, and shove your sincerity right into the audience's face!
Yes, there is a clear intention to manipulate the audience, especially its emotions, and as Eric Bentley says, to provide catharsis by a journey through fear and pity. The actor works with an aesthetic distance. Even anger must be an act of great beauty and musicality, like two Italian taxi drivers arguing over bent fenders; what a luxurious performance, filling the whole piazza! In this way, Melodrama has what is now popularly known as a "performative" aspect.
Melodrama is a way for student actors to learn about the possibilities of their own vocal and physical techniques; to explore them, to challenge them, to exploit them to their expressive limits, all the while exercising their "sincerity muscle." In a way rather similar to wearing a mask, Melodrama provides an alias that frees the actor to experiment.
Melodrama is an evolved style, generated by the actor out of a necessity to communicate and affect through the emotions. It was not invented by some clever fellow, and should not be imposed from above. To describe it as a "genre" is to place it in a prison.