I think Richard's work is successful when looked at in any number of ways. It could have been labelled as documentary or envirnmental or as cultural landscape or as probably a few other things, all without feeling like a stretch.
When someone chooses one label for their work to the exclusion of other possible labels, I assume that they're nudging us, for whatever reason, to pay more attention to one category of interpretations.
Kind of like saying, "this is the angle I was most interested in." Of course, it can also just be the angle that a publisher or dealer or customer base is most interested in ...
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