I think this is the best of Coetzee's novels that I've read. For a review (the best I've seen online, not that I've looked at many) see here. I find it hard to believe that The Road was not inspired at least partly by this story, which features a sort-of Christlike man on a journey through a land made hellish by war. He is Christlike in a very unpreachy way, though, and perhaps not obviously Christlike at all. I'm thinking of Nietzsche's understanding of true Christianity, the naive acceptance of whatever comes (which isn't quite how Michael K is, but it's close), or Dostoevsky's The Idiot, which I think inspired Nietzsche. He's also Schopenhauerian, being selfless and loving the world, compassionate toward others. Like the man in The Road, he carries something of great value. But what matters is his having it, not whether it gets successfully passed on to others. At times it seems clear that it will not be passed on, but that this is not something that concerns him. And his lack of concern comes to seem (to me) right. Then again it seems that it always was going to be passed on, because how could something so important or powerful just die out? This, as I see it, is the point of the passage with the doctor near the end, the part of the book that Cynthia Ozick regards as "superfluous." He sort of gets it and sort of doesn't, so that if Michael K has disciples they are almost bound to distort his "message." Perhaps just by understanding it as a message.
A striking, and odd, feature of the book is its references to Kafka, which come so often that I wasn't sure whether I was imagining some of them. Are we meant to think of "Metamorphosis" when K (who is subject to the power of people from "the Castle") is likened to an insect? Presumably we are. But then what is the point of hitting the reader over the head with these references? Is it to show that Kafka's world can be anywhere, even outside, even in the future or today, even in Africa? Is it to show that it is indeed everywhere, that we now live in an inescapably Kafkaesque world? Is it to downplay the influence of Kafka by making a joke out of it? Or is it to show that one can be literary at the very same time as being political and religious and philosophical? Or is it just how Coetzee thinks, sees things, and writes? Or again, is Coetzee a kind of disciple of Kafka who recognizes and confesses that he cannot be Kafka and so must follow without following, like the child he imagines in the interview with Peter Sacks who follows Bach's experimental steps ("try this") at the piano, until Bach takes off in a way that is beyond the child? I doubt there is a simple answer to these questions.
It's a great book though, and one I should just urge you to read rather than talking about it any more. One final note: the copy I read was from a library and had been written on quite a bit by someone with a red pen. Much of this writing referred to Kafka. So my interpretation of the novel might have been coloured by this.