I'm having a hard time understanding why this question was closed https://serverfault.com/questions/449735/inconsistency-in-a-popular-postfix-tutorial-about-directory-structure-for-virtua Of course this question wasn't about how good or bad the referenced tutorial is but rather about what should be a particular variable in a configuration file set to in order to support a specific directory structure for a mail server. Did I need to state it explicitly? What was my mistake?
Hmm. . .
Your question as originally phrased was basically "
$_TUTORIAL told me to do X in part 1, and Y in part 2, why'd it do that?", which is why it got stomped on -- the only way to reasonably answer this is for someone to take a few hours out of their day, set up a test environment, follow the tutorial, and report back to you.
To expect us to slog through tutorials and find errors in them for free is a little unreasonable (frankly it's mind-numbing enough that I wouldn't do it if you were paying me).
Having said that, I'm still not convinced this is a great question, but as edited it's at least tolerable, and our hedgehog claims to be able to answer it so I've reopened it.
Read about how to ask good questions
I spent a lot of time on that little diatribe, cribbing heavily from The FreeBSD project's guide on writing problem reports, which in turn cribbed from a bunch of other sources.
Following that outline doesn't guarantee you an answer, but making sure all of those elements are included (obviously, without us having to go elsewhere) helps a lot.
Often simply gathering that information will drop the solution in your lap.
As it stands your question is still missing a key element: Logs, error mesages, etc..
Always try it yourself first
Unless you've got a reasonable suspicion that trying something will be destructive, twiddle the knobs before asking us. (In your case flipping "NO" to "YES" might not have fixed anything, but testing it when you had the system set up has to be quicker than re-doing the tutorial, right? :)
Ask the right entity for support first
This is an ongoing pet peeve on Server Fault. People come here all the time expecting us to support a tutorial, commercial service, etc. -- We're not Tech Support for the Internet, and like I said above this is the main reason your question got stomped on.
It isn't that bad really, and a quick re-write would fix it. It would be better if you could re-forumlate it so that it didn't rely so heavily on me having to read the tutorial. For example you could have included the postfix/doveconfig config setting the PATH. You also asked the wrong question 'is this blog wrong', your questions should be asking 'how do I make this work on my system'. Yes we could assume that is implied, but sometimes we get overly picky
Did I need to state it explicitly?
YES, if you want good answers, then you should be explicit as possible about exactly what your question is. For the best results you need to ask the actual core question, so you can get the answer you want.
I downvoted and voted to close this question because, in its original form, it was asking a question which was best directed to the author of the tutorial. The heart of the issue, of course, being the ambiguity in the English language; the way the tutorial's author used the word "and" in "Mail will be kept in subfolders per domain and account" made the original question impossible for anyone but the author of the tutorial to answer.
Now that the question is answerable, I have removed my downvote and voted to reopen the question. I even know the answer and will be happy to post it; however I must warn you that posting rude and offensive comments toward the people from whom you're asking assistance is a very bad idea and you would do well to avoid it in future.