Recently, Michael encouraged you not to sweat the small stuff in queries and to understand that it's more important to write a great query than to worry about individual agents' pet peeves or assume that one false move will get you deleted without being read.
That's excellent advice, and I fully support it. But I've noticed over the last year or so that there's been an upsurge in the number of queries that seem to come through some company or program, rather than directly from the author. And that these queries tend to be sent to every agent here (and presumably every agent in some large database) and also tend to get filtered out as spam by our junk mail program. When I check my quarantined email, nearly every query in there has formatting that suggests to me they're coming from the same place. Lately they've been emails that begin with a salutation, proceed to a block of text with title/author/logline, and then begin a letter below. At one point they were emails where the logline was in the subject of the email. I've discussed this with other agents here and at other agencies, and we've all had the same experience.
Will I reject an author on principle if they use such a tactic? No, not really. A great query is a great query, and they're not always so easy to find. But while I have no problem with authors querying multiple agents, I don't think this is a good way to do that. For one, if it's getting trapped in our spam filters, it's probably getting trapped in many other agents', and that's not a good way to get read. Beyond that, if I sense going in that all my colleagues and the entire rest of the publishing world has the same query, I'm already less inclined to get excited about it. But mostly, it suggests to me that the author hasn't done any research and likely doesn't understand that certain agents and certain editors and certain publishers work with certain types of books.
I do think it's important to know where your book fits and to figure out particular agents you feel would be right for your book. I think that part of being a successful author is understanding the market and how it works. Much like when I submit a book to editors I carefully consider to whom I'm going to send based on what they're looking for, I expect prospective clients to do the same.
I don't discount the possibility that some of the queries I've received in this way were carefully selected for me and not sent to the whole wide world since I don't actually know how they're being generated, but if so, why lump yourself in with those people who really are just spamming the publishing industry? As an agent who gets too many queries a day to count, I recommend you send your queries to the agents you've carefully selected one by one. (Not that you can't submit queries simultaneously, because we expect that you will and I don't know any agents who have a problem with it, but that each query should be sent in a separate email to a particular individual.) Sure it takes more time, but if your writing career is not worth investing time in, then why would you even bother? And, to be honest, why would we?
Or course, as Michael mentions in his post, I'm almost certainly preaching to the choir here! If you're actively learning about the goings on of the publishing industry, this may well be advice you don't need. But if you could shed any light on where these queries are actually coming from, I'm all ears!