Actually, it really does help.
Little tid bits of information get stuck behind from your programs folder, and a few other things. Sometimes, it will not cause problems, but for the most part,it really does help.
ESPECIALLY if you use a rom like NFSFAN's. He mods TONS of items throughout the entire phone, and that causes most of the problems when flashing to a new version.
I've lived by hard resetting, flashing 2-3times, and then good to go.
I've never had the problems that most people report on this website and xda.
If you read all of my posts, about 50% of them will be something along the lines of weird, I've never had this problem.
Also, another problem that occurs while flashing is having other programs running on your computer while you flash, it bogs down the RUU and can cause problems while flashing.
Just because it's suppose to cover all of the old information, doesn't mean it will.
Things don't always work as they are designed to, I mean, look at the U.S. Government.
