Wow, I was not expecting such a huge amount of comments.
I've updated the article based on this. Most importantly, removed the proprietary part - indeed, that has nothing to do with the howto. This intended to be a howto, not a troll text. I just wanted to add some background to it, for better understanding.
Create a second account, use it to shrink primary account (useful regardless, for many other troubleshooting reasons.)
... and keep that in sync with your primary account. Seems like a lot of work to me.
And how often do you log out of your Mac?
If you are using time machine to make backups, you have to log out to back you your homedir. This means, you are forced to log out as often as you want to save your work.
Don't compare floating point numbers solely for equality.