Pre-empting Reflections

Yesterday I bought a copy of Reflections, the Walter Benjamin collection. I'm happy to have the book, but now I sort of wish I'd held off and perhaps tried to find an older, used edition. See, I bought a copy of the new edition, issued in 2007. The cover is uglier than the old one was, for one thing. Far worse, it's saddled with a new, worthless, three-page preface from one Leon Wieseltier. Has a preface or introduction ever made you want to unload a book you're otherwise happy with having? Is it wrong that I want to take a blade to these pages? Wieseltier isn't around for long and doesn't say much, but characteristically, he does have time to irritate. After a relatively innocuous opening page, we get this:
In his temperament and in his method, Benjamin was an esotericist. He was modernity's kabbalist. In his turgidly enchanted world there were only mysteries, locked and unlocked. His infatuation with Marxism, the most embarrassing episode of his mental wanderings, the only time that he acquiesced in the regimentation of his own mind, may be understood as merely the most desperate of his exercises in arcane reading. . .

[. . .]

. . . Benjamin's work was scarred by a high ideological nastiness, as when he mocked "the sclerotic liberal-moral-humanistic ideal of freedom" (as if Europe in his day was suffering from a surfeit of this), and speculated acidly about the belief in "the sacredness of life" (or from a surfeit of this), and responded with perfect diffidence to the censorship and persecution of writers in the Soviet Union, which he coldly described as "the transfer of the mental means of production into public ownership." The pioneering explorer of memory worshipped history too much. He also wrote too much: he advised writers to "never stop writing because you have run out of ideas," and often he acted on his own advice. I confess that there are many pages of Benjamin that I do not understand, in which the discourse seems to be dictating itself, and no direction is clear. Like many esotericists, he abuses the privilege of obscurity.
What is the purpose of such a preface? The book still has the original, 35-page introduction by Peter Demetz (who, to be sure, does criticize Benjamin in certain ways, including aspects of his relationship with Marxism, but who isn't dismissive or obnoxious about it), which should do a well enough job by itself introducing the new reader to Benjamin (especially when combined with Hannah Arendt's introduction to Illuminations). Why is Wieseltier here? What purpose can he serve, other than as an attempt to pre-empt the novice reader's own readings? This Benjamin character is an interesting read, when it comes to literature, sure, but be sure to not take him all that seriously otherwise! (But, you know, thanks for buying our book!)