her willingness to invent the content she ascribes to poets and then discover it tends to carry her to not their most sparkling lines.
Maybe their most sparkling lines wouldn't be a very good place to start though honestly.
This is an interesting pitfall of the review-essay. A periodical like, say, the New York Review of Books invites important people to review books at great length. Their essays are later collected into books, which are expected to have a measure of organic integrity and to be important works of criticism.
These aims are not entirely consistent. There are three types of audience for an essay about a book of poetry -- 1. those to whom the poet is new, and who would like to know what his work is like; 2. those who know the poet's earlier work, and want to know how the new book compares with it; 3. those who have read the book. A review-essay, qua review, is meant for 1. and 2.; qua essay or chapter of forthcoming book, for 3.
When I read a review, I expect a generously illustrated description of the writer's style, and a fair account of his (or her) sensibility. This does involve quoting the brightest passages, because -- like most people who still read poetry -- my first question about any book is how well it's written, and the high points are relevant evidence. When I read an essay on someone whose work I know, I'm looking for an angle on the writer -- or on modern writing and how he fits in. In this case, Zach's right: the obvious starting points are crap.
So how does one reconcile these things? Auden had an ingenious solution that worked for him in Forewords and Afterwords, but probably wouldn't for anyone else. As John Berryman wrote:
It is hardly unfair to say that Auden, over the years, has done one of two things with books entrusted to him for comment: either he wrote about what interested him at the moment, making some spidery connection with the book in hand, or, with books he felt keen about, like Cyril Connolly's vivid Enemies of Promise, he quoted from them at agreeable length.
(The book, as a result, is an excellent piece of Audeniana.) Or one could, like Vendler, give a themed guided tour of the book -- a "Phallic aspects of Chicago" -- that includes its high points and also fits into one's overall interests. There is some misrepresentation involved here, no doubt, but the point is to get people to read the book, which they will if the quotations are appealing enough.
In my experience, Vendler's are. But this is all extremely subjective.