I've noticed recently that when I write a new question such as this one, the "Similar questions" box just above the Body text entry box shows results that are similar, but they're similar for the wrong reasons. I format my (self-study) questions the same way: problem statement (including which question and which book I'm asking), my work so far, and my question. You can see that if you look at my last 10 questions, at least.
Here's the problem: the "Similar questions" box, which I rely heavily on to know whether I'm asking something that's already been asked, has lately been returning almost all questions that I've asked before! If the question I'm currently writing is that similar to previous problems, I wouldn't be very likely to ask it. I'm guessing that the ML matching algorithm is picking up on my formatting and keywords like the textbook I'm studying.
Here's a proposed solution: the "Similar questions" box should at least limit results authored by the same author as who is writing the current question, if not exclude them entirely.
[EDIT] Per whuber's suggestion, I have re-posted this to meta.so.