Ian you bring quite a few salient points and I am confident your post will impact some reflection and discussion with us all. So, in summary, for the most aspect, I do pretty agree with the view that most art does not try to convey a distinct which means from the artist to the viewer, I do not agree with universalizing the conclusion to the point of suggesting that it is can not or does not come about. An artistic medium is the substance or material the artistic function is created from, and may possibly also refer to the strategy employed.
I surely consider there is place to explore which means in art at the elementary level, specifically in moods and feelings when it comes to color. I stopped reading that abhorrent mess simply because the articles were so poorly written that it would take at least two times to read any offered write-up to realize what the writer was attempting to convey. To address one particular of them, I believe the significance of ancient art (Egyptian, old spoons and the like) is the history of art itself.