The Art of Flirting is absolutely, utterly banal. Completely insipid.
Let's begin with the much-vaunted dialogue. I understand that the dialogue was workshopped, but the end result is still flaccid and disappointing -- no different from just getting the actors to sit around and just talk. No indication whatsoever about the characters' motivations or personalities. The dialogue is uninspired and meandering.
The trick with dialogue-heavy narratives is to create dialogue that sounds plausible, yet also serves a dramatic purpose. At a basic level, dialogue advances the plot. Better writers are able to make dialogue reveal bits of character so that the audience will be able to react in some way. Conversely, pointless chatter in a movie may be "realistic", but it's completely uncinematic. If I want realistic dialogue, I'd go sit in a Coffee Bean for a few hours.
The point is not to be realistic, but to give the impression of realism. Sadly, this film is a gross example of how the former can be hopelessly confused with the latter.
The camera movements were the worst. "Erratic" does not begin to describe the camera movements, with shots that were clearly off for no dramatic reason whatsoever. "Hummingbird on LSD-laced speed" is a better description, and even then hummingbirds stay in place sometimes.
But hey, it's director Kan Lume's first film after all. Hope the next one's better.