I did not really understand the benefit in comparison with a sock-puppet account linked to a throw-away e-mail address. That's the universal way for any web registration form.
Just in case there's any data leakage.
Really? The only information I know of that gets into a commit is your name & email and the current time, and the first two have to be configured before you can commit.
If you're on a linux machine, usually it can't, so it pops up the "set your global user and email" prompt without committing things.
If you're on a domain windows machine though, often it can. When that's the case, it does the commit first, and then asks you to set the config explicitly. You then swear, change the config to be blank, and then go amend the commit you just made.
In any case, the whole thing is a pain that adds mental overhead I'd rather spend on programming.