You shouldn't assume the user has found the canonical post. Either because they couldn't find it, or they didn't look, or it not coming up when they wrote their title* because the canonical one is too generic... There are many reasons people don't find the big posts.
If you want to give them the benefit of the doubt, assume they stuck "ubuntu upgrade" into Google. The first result is an Ubuntu.com page:
URL looks good. Content is clear enough but it's extremely simple. The user said they were having issues (this isn't a simple "How do I upgrade?") and look at the bottom of the Ubuntu.com instructions:
And if you get stuck… Ask Ubuntu
Neat for us, but rather than giving them better documentation (which already exists) we're pushing them at a support site where people are expected to ask questions.
We should either be recommending that Ubuntu.com links to specific questions, or that Ubuntu.com links to the Ubuntu Wiki which then links to us in a "And if all else fails..." gesture.
And on the subject of canonical question quality, there are two exclusive states a good post can fit into:
- Canonical, thorough but a long and over-achieving
- Concise, easily digestible but won't cater to all edge cases
You can't really do both in one question. Thankfully when somebody asks a specific question, we can give a concise answer and link to the second.
We don't need to dupe everything against a canonical question. We should strive that there's only one or two 13.04→13.10 upgrade questions but having one or two of those means that users in the future will be able to find the right thing.
*The title search is awful. Put "upgrade 13.04 13.10" into a new title and none of the posts that come up seem useful or relevant.