Well the whole issue with mental illness is it more often than not includes an inability to control how you feel or all your symptoms and how you react, that is why people with mental illnesses can usually use some sort of help. Ignoring that fact is probably more dangerous than promoting it...it doesn't mean mentally ill people are dangerous at all times or that all are, but yes the symptoms can sometimes make one dangerous to themselves or others....it is shown though that symptoms are worse under stress so obviously reducing stress or teaching better coping techniques if possible could reduce that. Sometimes one can learn to have more control or manage symptoms but not always it depends on the severity and the individual.