The title of the thread is the question. I actually found the video to be delightful. It's only three minutes. He's not giving you an MFA lecture; he's just touching on the subject. I happen to find reader response theory interesting when it comes to critiquing. Many people focus on the nuts and bolts and mechanics of the work without really telling the submitter how it made them feel. Inline critiques over at Critique Circle allows people to give feedback as they're reading. I think that's pretty cool.
That's nice. However, what you actually did was link-drop. And while it's great to call attention to a useful resource, there are some problems with the way you did it and the resource.
1. He's not a prof, which you seem to suggest he was.
2. You don't really understand reader response theory in part, because he doesn't seem to either. That's ok though, because it doesn't actually offer anything that a reader can't do without knowing lots of nifty jargon from critical theory.
3. You're actually asking about a feature from another site which you don't explain or provide a context for; that's going to cause confusion for your readers.
4. Critical theory is about methods and tools for engaging in literary criticism. Literary criticism, unlike a critique, is not about the work/the text;
it's about the reader. It's not terribly helpful in general to the writer of a work.
5. Reader response theory while great fun for the reader of a text, doesn't really help writers much because, despite the video and your own desire to make it mean "how the work made the reader feel" isn't what reader response is about.
6. The core concept of reader response theory is that there isn't an actual text. What the writer wrote, what you read, what I read and what Jennie Doe read are all different texts. There is not central shared text; the text is different, entirely, because each reader is different. Perhaps the best example of this is that the second central text in terms of engaging in reader response theory, after Tompkins' Reader-Response Criticism: From Formalism to Post-Structuralism, is the work of her spouse Stanley Fish,
Is There a Text In This Class. Telling a writer that there is no central text, no shared meaning, is more often than not perceived by writers as a useless exercise in frustration, because it simultaneously renders all feedback, all responses, from readers as equally valid and equally invalid.
7. The assertion that "Many people focus on the nuts and bolts and mechanics of the work without really telling the submitter how it made them feel" is not about reader response theory; it's about a poorly presented or poorly understood crit.
8. A preponderance of crits talking about "nuts and bolts and mechanics" may be that the work is so difficult to read because of those issues that the readers can't really make sense of the work. If there are a lot of mechanical issues, or nuts and bolts issues, the piece may have been posted a bit too early for crit.