* Even if I can't remember the exact phrasing I used for something, I often remember the person I discussed it with and just check my DMs or threads with them.
* Half of my responses to "help me" questions include links to repos in files. So I search for the last time I typed out three paragraphs talking about a a given link and that works pretty well.
The other situation "type it out" is useful is when I think a particular problem is likely to be encountered by multiple people and essentially force someone to ask the question in a public channel so I can answer it there and everyone can see it (we have channels like and #new-eng-questions for this). Even if people don't find it via search, there are enough people checking the recent history of these channels that it's a useful exercise.