I took a grammar class in college, not to help my writing but to help my tutoring; there were too many times when I'd say "I feel like it should be this but I can't tell you why" and this was, to my mind, Unacceptable.
While it definitely helped my tutoring, I found that it helped my writing even more than I expected. That's because my professor presented everything as options: here are rules, or at least guidelines, and mostly you want to follow them, but once you've learned what they are and why they exist that way, you can choose when and how to break them. It made so much sense! It was so practical, so helpful!
I feel like adverbs are one of those things like first person narrators, where anybody can use them because they're easy, but in fact they're difficult to use well. And I like that idea of "think twice before" or "stop and think before" because it's not that you can't or shouldn't use adverbs (or first person narrators), but that ideally you should stop and think about why you are making that choice instead of a different one, and what (if anything) it adds to the story.
(I should say, I have nothing against first-person narrators--there are many of whom I am quite fond--but they have a lot of specific advantages and disadvantages that may not be obvious until you stop and think about how they function in a story. Or at least, I didn't really think about them until Alpha or whenever it was someone first pointed this out to me.)