If an agent answers a query (or responds to a submission of, maybe, a synopsis and a few chapters) saying "No thanks. Not right for me" -- or "I didn't fall in love with it, so can't see representation," is it ever permissible to ask for suggestions, explanations, pointers? Or have agents got much better things to do with their time than coach someone whose work they don't particularly care for?No
I'm not a writing coach or an editor. There are many other places to get that info. And sometimes there's nothing "wrong" it's just right for that agent.
You don't want to pay for stamps (since you're the same person who posted that comment about having agents pay for reply letters) and now you want me to respond individually to your query. I get 100 queries a week. It would cost me 45cents in paper and ink, and at least twenty minutes for each query to offer even rudimentary suggestions.
Forget the $45 in paper and ink: that's 30 hours. How many hours a week do you want me to work for free? And once I've spent that 30 hours giving you suggestions, is that when I settle down to actually do work for clients..the clients whose work brings in the money to pay for the ink and paper and stamps you think you shouldn't have to pay for?