There are good reasons for all the steps in that tutorial, and while not all are necessary all the time, if you follow the instructions, nothing bad will happen. It’s not a hard upgrade, but that doesn’t mean you can be careless and just drop the new files in there. After all, you no doubt have modified many files in order to customize things to your liking. The good news is that the structural changes (such as putting your customized files into a “theme”) will make the next upgrade easy as pie. I upgraded my site to 1.3 and then 1.5, so lately, I’ve been able to upgrade to the latest nightly version just by dropping the new files in. So make sure you make the necessary changes… it’ll really make life easier.