Handwriting analysis certainly used to be a big part of the hiring process in Europe as well as at some US companies. They do the analysis primarily to weed out the trait of dishonesty, which is an easy one to spot. Some companies probably still use handwriting analysis - although cursive is being taught less and less these days, and I can see the time coming when cursive will die out completely.
Sloppy handwriting does not necessarily indicate a "bad" personality or a "schizophrenic." For example, the American serial killer, Ted Bundy, had perfectly flawless handwriting. Like a typewriter. The kind of writing that shows a brilliant and focused mind. Unfortunately, you can't tell from someone's writing if they are a killer. You can tell if they might have argumentative tendencies, sometimes you can tell if they are physically or mentally impaired or using drugs. You can even tell if the person is emotional. But a psychopath like Bundy is so adept at blending in and appearing normal, that even his handwriting appears flawless and "normal."
From Snowden's handwriting, I see someone who is going through a lot of emotional turmoil right now, but who has a great deal of determination and is an honest person - not a liar.