The edition I read has an excellent introduction by Mick Imlah that makes a hard but fair assessment of Muir'a late development, his seeming disinterest in words for the own sake, and his efforts to find a pattern of human life in the mess individual lives around him.
With the weaknesses of Muir's approach having been flagged in advance, the reader is then free to discover its considerable strengths for themselves - a long walk up a sometimes unspectacular hillside, but man, what a view at the top!