The online editor of the Scottish Review Of Books, Harry McGrath, recently posted a blog in which he asked, "Is there another Scottish literary renaissance, or are reviewers just being nice?" His comments were sparked by reading the Scottish literary magazine Gutter, whose reviews he says are almost all highly complimentary, and certainly never harsh. As McGrath writes, "Read collectively... the reviews give the impression that most books published in Scotland these days are somewhere between good and great."

Such generosity is particularly unexpected since the reviewers are anonymous. For many this would be ?¨a licence to let rip, like twitter trolls ?¨or the sort of cowards who leave nasty comments on newspaper or Amazon websites, safe in the knowledge that their name is withheld. But rather than acting as a cloak for a dagger, Gutter's pseudonyms make one wonder instead if the writers are friends or associates of the authors under review.

In reply to McGrath's piece - in which he concludes, a little unconvincingly, that perhaps it is best overall to be positive and encouraging - Gutter's managing editor Helen Sedgwick has given a spirited defence of the magazine's policy. Her main reason for running upbeat reviews is that since the magazine is published just twice a year, and can only cover about 10 books at a time, she prefers to highlight good books rather than those that are seriously flawed: "At Gutter," she writes, "we just don't like a waste of space."

I share Sedgwick's loathing of the hatchet job, the sort of review that creates headlines and makes the reviewer look exceedingly clever, if nasty. Her refusal to run such pieces ?¨is understandable. A critical review, however, need be neither scathing nor cruel. The best reviewers use a stiletto not an axe when skewering their subjects, bringing their experience and insight to bear on their assessment, and expressing their reservations clearly and constructively.

Generally, it is the public who loves vicious attacks, not the editor of books pages. And most reviewers take no pleasure in denouncing a book. It is not that we worry that saying unpalatable things makes us unpopular - that, sadly, is an occupational hazard. It is that reviewers know how much work goes into a book, even a bad one. We do not pour cold water on them with glee - quite the reverse. It is dismal enough pointing out the failings of a writer one has never read before, let alone of a figure one reveres.

There is consolation, though, in the fact that no good writer has ever escaped entirely unscathed from critics over the span of their lifetime. Also, an author's career is long, and bad reviews are an inevitable part of that. The writer whose track record ?¨is unblemished by a dud or a near-miss is almost unheard of. One should, rather, expect the occasional flop.

Ceaseless praise or outright sycophancy, then, is ultimately destructive, not only to the author but to ?¨their rivals. Not only does ?¨it distort the culture in which a writer is working, but it sets an artificially low bar and kills ambition.

While writers on the receiving end of reviews might warm to the idea of ?¨a stable of reviewers whose claws have been sheathed, I would suggest that solely featuring good books undermines the main principle of book reviewing: namely, to give honest and fair ?¨criticism across the spectrum of ?¨what is published, and to offer ?¨readers a purview of the literary field, regardless of whether they ever read the books under discussion.

Established authors no less than rookies deserve to be treated seriously - and that includes being challenged if their work does not reach the expected standard. As an editor, I will run tough reviews if they are fairly argued, and do not arise from personal enmity. Occasionally, of course, one discovers too late that there was a private animus between reviewer and author, or a hidden agenda that was never declared. Yet such cases are rare. As, thankfully, are irredeemably bad reviews. Most are more balanced because, like literature itself, critics should offer darkness as well as light.