After all, there are enough stories about great directors who were impossible to work with - but the stars put up with it because the results were so brilliant. I don't think Kéchiche has quite reached that level, so I agree that he went too far, further than it was wise for him to go - but as for "total idiot", I don't know.
Fair enough, but that shouldn't be a reason not to see it.
It was a scandal movie in the sense that, as I recall, it is or was until recently the only movie to get more viewers in Sweden than Titanic - which it never would've come close to achieving if the romance had been straight. Not quite the same level of fame elsewhere perhaps, but still probably among the most famous Swedish movies, other than Bergman ones (or even including Bergman ones, perhaps).
But yeah, it was an innocent and indeed charming movie, though I wouldn't exactly call it a "teen comedy" either.