Exactly my friend, we the so-called 'Normal' people stuck with our own social delusions; varied in seriousness; like believing that animals's main reason for existence is to be our food or in minor issue like wearing black is bad omen for Chinese though the English would think of it as formal (as in "Black Tie party").
I have not see any case of mental disorder patient eating stone before but yes I do read about their killings. Then again, the so-called 'Normal' people kills too... due to anger, greed for money, jealousy or ignorance like cult followers or hatred to a particular race/ ethnic, etc.
What is 'Normal' behaviour? I don't know if eat gold paper like in Japan or wearing, acting and drinking blood like the Vampire Nation (Vampyre Nation) in US, can be considered as normal?
http://www.vampire-nation.com/
The point is, WHAT is NORMAL and what is NOT?
We all live in our own delusions. The shared delusions are deem as normal. If you are different, you are abnormal, schizophrenia or not.
I'm not debating on medical conditions or definition for schizophrenia but to look at it with different view, the Buddhist view.
In the Buddhist view, a person with mental illness that is irreversible such as downs syndrome or autism is considered as someone with incomplete mental faculties and can derive very little benefit from the Dharma. A person with Schizophrenia for example is bombarded with hallucinations day and night, to the point where they can no longer tell what is real or not real. They cannot even tell if the Dharma that they study is real or not! So, their mental faculties are no longer functioning. If their mental faculties are not functioning, then how can they be considered normal if they are unable to even do their daily tasks? What I am trying to discuss here is how Dharma can heal possibly reversible states such as depression, bipolar, borderline personality disorder, dissociative personality disorder and schizophrenia because Buddhism seems to have that effect.
Now... is he or is he not healed? Again, this is a very subjective view. My point is, don't jump into conclusion too quickly... or take anything at surface value, nothing is definite.
In this case, it is not subjective. The word Schizophrenia means two minds, and a huge symptom is incoherent thoughts and writings or speech: fragments of thoughts and words strung together but do not make sense. The "conclusion" part of the story, does it not sound that way? Do draw your own conclusions 
Hi DS Star, it would be great if you could read up on what mental illness is because many Buddhist masters actually do not recommend people with mental illnesses from using Buddhism as a quick fix and usually ask them to get professional help first. Everyone is deluded, else we'd still all be Buddhas, but that is very different from mental illness. Mental illness is a damage on the mental faculties that prevent that person from functioning normally.
