“Sometimes I use a pseudonym Is there something that could possibly be construed as a conflict of interest by picky cyber-trolls? Then I write under a different name. There never is a conflict of interest, by the way, I’m always as subjectively objective as I can possibly be (or do I mean objectively subjective?), sometimes to the point of personal detriment.”I can understand why reviewers might be tempted to use a pseudonym, to avoid all the hassle. People who get bad reviews have a tendency to assume there must be a reason for it (other than the obvious), and sometimes bear a grudge for years. We're frequently accused of having it in for people, and our reviews are only read by a handful of people, rather than the tens of thousands who read SFX.
But if you think people might perceive there to be a conflict of interest, surely the answer is to mention it, or hand the book over to someone else for review, rather than disguise it with a pseudonym? That's how I ended up reviewing Bob Lock's The Empathy Effect for Black Static; Peter Tennant felt there was a conflict of interest, having done a bit of work on the book, and asked me to pinch-hit.
Maybe it's because I spend most of my time working on legal books, but I can't help imagining the reaction if a retiring judge were to mention, casually, "Whenever there was a risk of looking biased, I just gave judgment under a pseudonym to avoid complaints from picky human rights lawyers..."
In the legal system, it's essential to avoid not just bias, but also the appearance of bias, for obvious reasons. In a review that isn't strictly necessary, because there aren't the same consequences: it's just your opinion about a book, and the reader is perfectly capable of taking your biases into account, if they're aware of them.
There are many good reasons for using pseudonyms (to be honest I wish I'd used one for all my reviews from the start, so I could go to conventions without fear of getting punched!), but a reviewer using a pseudonym specifically to conceal a perceived conflict of interest is, I think, deliberately misleading their readers, even if it's with the best of intentions.
There was quite a row last year when a pseudonym turned up in the first issue of the BFS Journal, and in the course of that discussion I said pretty much the same things. I have to admit, Guy Haley is a much more experienced reviewer than I am, so there are bound to be some aspects of this I haven't considered, but I hope it isn't a widespread practice.