Continuity can often determine whether multiple cameras have been used to capture the scene. If the action matches up well you can presume that the footage is taken from a single shot with multiple cameras recording the same piece of action. The editing has been done in the editing room and this gives the scene more freedom as you can cut between the different angles at any point you like without having to worry about cutting out certain inconsistencies and ensuring that the action matches up.

Shooting from behind often gives more of POV perspective. When shooting dialogue between 2 characters it can be more intimate as you see what the character sees. It also often enables the camera to get closer over the shoulder shots with the other character dirty in the frame. This can help build and strengthen relations between the audience and characters. It can give more of an insight to characters emotions and make them appear more vulnerable and therefore endearing to audiences.

If I was compiling shots for a film I would be worried about the overall edit looking disjointed. It is important to be able to get a balance between having enough different shot sizes, angles and movement to create intrigue and give a naturalistic, or other desired effect. This needs to be done whilst maintaining continuity and consistency, you don’t want to leave an audience feeling dizzy. You don’t want to distract them from the action that is occurring by requiring them to reposition the characters and take a moment to reset their understanding of the shot composition before they tune back into the dialogue.