•The original problem is benign - I've yet to actually be affected by it in any way, other than the minor annoyance of seeing the duplicate top-level entries.
•The solution is more annoying than the problem - That list of instructions is fairly long, and in areas most people rarely deal with on a regular basis. Duplicating email account definitions by hand is one thing if you have only one account - I have seven defined, and I would have to re-enter each by hand, since Outlook has no import/export of account settings.
It's important to note that this is not a problem with the PST, and does not cause your PST to double or triple in size. It's just Outlook's way of looking at your PST that appears slightly messed up.