I went through the same thing as the commenter above and it was OBNOXIOUS. Even worse, there's no real reason for it be done the way it is.
Oh, and then I realized I'd made a really stupid (but easy to make) mistake that altered the amount I owed by $12 and had to file an amended return.
Really really obnoxious.
I'd bet anything people would care 10x less about getting taxed if filing weren't such a hassle.