I love people who make me mad enough to think through an issue for myself. That seems to me the function of the essayist -- to kick-start your own processes of meditation. Gabriel Gudding's essay on the evolution of contemporary poetry is a splendid example of the kind of writing that gets you mad enough to engage (or at least it did me). Mad as in a rage of interest and self-debate. As in "what is he talking about -- does he know what he's talking about? -- wow! what he's talking about" kind of thought-train. I'm still steaming along on it.