I don't really want to deal with the schizophrenia article because frankly, the way it's used in the debate, it's hard to have a fair and honest conversation about it other than: "The science is weak because no one CAN know because it's fucking illegal to study." (er, this sounds like a dismissal of the article, please don't take it as such, it's not meant to be)

That having been said, I think that it is different than what the GP was referring to which is a chemical addictive property (like nicotine) rather than a long/short term side effect (smoking side effects, whether it be tar in your lungs or increased risk of schizophrenia)

[1] Sorry for the language, but the biggest joke of this entire debate is that Cannabis is a schedule 1 drug.