Thank you for the sources, however the Royal College of Psychiatrists link contains a lot of outdated references and seems to be written in a way to scare parents into sending their child to a psychiatrist (psychiatrsits have to make money too). Your second and third link contain no references/sources to its claims.
In regards to your skunk example, THC is a psychedelic attribute of weed, and it can cause effects similar to mild psychosis - but they can be very broad, things like confused or fast thoughts, changed feelings, hallucinations. The researchers of the study asked the volunteers questions like "Do you feel you have to hide certain things about yourself to others?" Well, if you're taking an illegal drug then you are likely hiding this fact from people, they also asked: "Do you ever feel like people are out to get you, or that people would judge you if they knew what you were doing"? If you're doing something illegal then there are defintely people out to get you. These aren't delusions due to psychosis they are describing reality.
It's not true that skunk strains contain no CBD, however the anti-psychotic properties of CBD are interesting and could be used to help treat people with psychotic illnesses. This means weed strains could be breeded specifically for psychotic patients.
"Real life studies also show that people admitted to psychi hospitals with drug induced psychosis are 7 times more likely to be skunk users that users of other types of cannabis."
How was this proved? Because it's illegal, it's very difficult to tell if you're smoking skunk or a different strain of weed just by smoking it (there are potentially infinite strains due to breeding possibilities). Dealers will often hype their product up by saying they have skunk when in actuality it's something else, but they can do this because it's an unregulated market.
Schizophrenia/psychosis rates are not consistent with weed consumption:
"Increased cannabis use by the public has not been followed by a proportional rise in diagnoses of schizophrenia or psychosis, according to the findings of a forthcoming study to be published in the journal Schizophrenia Research.
Investigators at the Keele University Medical School in Britain compared trends in marijuana use and incidences of schizophrenia in the United Kingdom from 1996 to 2005. Researchers reported that the "incidence and prevalence of schizophrenia and psychoses were either stable or declining" during this period, even though the use of cannabis among the general population was rising.
"[T]he expected rise in diagnoses of schizophrenia and psychoses did not occur over a 10 year period," authors concluded. "This study does not therefore support the specific causal link between cannabis use and incidence of psychotic disorders. ... This concurs with other reports indicating that increases in population cannabis use have not been followed by increases in psychotic incidence."
The results of a separate clinical trial published earlier this month reported that the recreational use of cannabis does not stimulate the production of dopamine in a manner that is consistent with the development of schizophrenia."
Source: www.ncbi.nlm.nih.gov/pubmed/19560900
The illegality of weed means that people who are willing to go to jail control the market, and this market is almost entirely driven by profit. People are out to make as much money as possible and can endanger people's lives in cases of gangs or the product where contaminants are used to increase weight to make more money. If weed was legal, it would be harder for your son or daughter to acquire it as there would be an age restriction - dealers don't ask for ID. If it was legal it could be regulated, information about THC/CBD levels would mean people could purchase a strain more suited to them. There would be no contaminents, it would be cheaper and also taxed which would provide a huge amount of tax money being that it's currently the most used illegal drug. Less people would use alcohol as they switch to a safer drug so no wonder alcohol companies want to keep it illegal.
Do you feel it should be illegal?