So you guys think that if I said "please stop telling me to update" it would discourage reviews other than the ones that only consist of "Please update!!!"?
Yeah, weird, isn't it? I guess it's kind of a psychological thing. I really think the people who type "UPDATE SOON!!!!!" ten minutes after you've just posted a chapter aren't the type to adhere to, or even read, authors' notes or instructions. And the more conscientious people, who do
read that, might feel chastised and thus discouraged from reviewing or even reading more of your work. I mean, if someone wrote you a nice three-paragraph review and at the end said, "I hope you'll update the story soon!" you wouldn't be upset about that, would you? But that person might read a note of "please stop telling me to update" as being directed at them, and feel stung.
I mean, the wonderful thing about fanfic is that it's all done for free. You can write and post it for free, and you can read it for free (and anonymously), and you can review it for free. It all kind of runs on goodwill, I think--like any hobby, people do it (reading or
writing) because they love it. Now granted, these yahoos who just demand you update to suit them are sapping your
goodwill as a writer; but I think if you try to tell people how to review your work, in a negative way, you
risk sapping the goodwill of your serious readers. And the yahoos probably won't be affected one way or another.
Perhaps you could phrase it positively--"I really love thoughtful reviews and take reader feedback into account with future chapters! If you could just leave a few sentences telling me what you liked or didn't like about the story, I would really appreciate it."
Or, if you're in the market for some serious, in-depth analysis of your writing to help you improve, I'm sure there are some dedicated groups for that, which you could post to instead of/in addition to the less-regulated environment of fanfiction.net.