Of course, it would be interesting if the artist could then explain what he really meant, but only after we've tried to guess.

That's exactly what I think. Usually at openings you can get an explanation from the artist, but I don't go to openings because there's a crowd and I like my experience to be untouched. When they tell you what you're going to see, you will no longer form your opinion, but go on with the artist view and I don't want that. After visiting the exhibition, yes, than it would be nice to know, but that never happens :)