From the site rules edits should be reserved for making a question clearer from the readability and interpretation point of view like fixing typos, bad language, or poor explanations.
When should I edit posts?
Any time you feel you can make the post better, and are inclined to do
so. Editing is encouraged!
Some common reasons to edit are:
- to fix grammatical or spelling mistakes
- to clarify the meaning of a post without changing it
- to correct minor mistakes or add addendums / updates as the post ages
- to add related resources or hyperlinks
Tiny, trivial edits are discouraged - try to make the post
significantly better when you edit, correcting all problems that you
There is no specific mention about making it easier to find, maybe because 'easier to find' is possibly subjective.
While I would not condone such editing per-se, it is a highly personal subjective matter; the terms and words you used to find such answer may mean nothing to someone else, or even inadvertently make it harder to find by having it pop up in unrelated searches.
It is true that Stack exchange search is not the best at times, and I have frequently found myself searching through Google instead to find answers here.
So my suggestion is, if you can, improve the tags of such question, fix any misspellings, lingo, technical terms and official names (modifiers, tools, operators, UI etc.) as per the Blender Manual or optionally commonly used terms among users, but don't just add random text to answers.
Maybe if necessary do it in the comments section instead, preferably in an intelligible and constructive way like say posting a comment along the lines of:
This answer may also be useful for seamlessly joining mesh(es)
Hopefully comment texts are included in search results thus achieving in your initial intent.