Often, in order to discover information about the functionality of the Stack Exchange software, I search here on Meta. For example, recently I had a question about flags. I found the answer to my question while searching Meta, but in the process I heard about a new type of flag I was unfamiliar with: the "invalid flag flag".
Now, trying to search for information about this flag left me very confused! It's not an easy thing to search for, and it's not in the FAQs or the like. The reason, of course, is that the flag no longer exists; after a good deal of time spent searching, following around links, etc., I found this answer which explains how and why the flag was removed (and strongly implies information about what the flag did when it existed). So that's the answer I'd have wanted to answer my question.
This situation is a bit unsatisfactory, as it's hard to find the answer to the question by searching, so ideally I'd want to improve searchability a bit. There are two obvious ways to do this:
Ask a question and answer it myself. However, it seems common (unless I'm mistaken) to close questions about a feature as duplicates of the feature request (as the answers describe the new feature). Intentionally posting a duplicate seems to be discouraged on Stack Exchange (even though the equivalent is encouraged on many other wiki-like sites; for example, Wikipedia encourages its users to post redirects in order to improve search results). As such, I can't really do that.
Edit the question to make it more likely to come up as a result of the search in question (this is recommended in the post I linked above about intentional duplicates). However, that's very hard to do on a feature-request, because the question is (and should be) written as though the feature doesn't exist! Placing something like "What is the 'invalid flag' flag" in the text of the feature request would be nonsensical.
So in other words, if people treat Meta the same way they'd treat, say, Stack Overflow, this sort of unsearchability issue would end up never being fixed (this is a consequence of the strange property that Meta has that answering a question can often change the context of the original question). As such, my question is: should we be encouraging people to fix this sort of unsearchability issue on Meta, and if so, what method should we use to do so?