Yes you can die from weed. Just because there are no recorded reports does not mean it not possible. And i guess you could say i have "overdosed" on weed in that i smoked so much i was uncomfortable and had many negative effects. In respect to toxicity, opiates/opioids are the least damaging to the human body compared to weed, cocaine, alcohol, meth/amps, ketamine, and, god forbid, bathsalts. In reality, diamorphine should be schedule II as it has medicinal use (replaced morphine in the UK for a long time). If anything it has more medicinal uses than ethyl alcohol. If illegality, scheduling, and over all bodily damage were the criteria for how "dangerous" a substance is, weed is worse than heroin
I'm sorry but that's stupid. I can give you a money back guarantee that no one will ever die simply from the direct effects of marijuana; you know this, but choose to be nit-picky with technicalities. Thousands die daily from taking opiates/opioids, probabaly more so than your whole list. This is reality. Reality lays waste to hypothetical truths.
How about this: people suffer ten times more physical/mental damage from taking derivatives of the opium poppy than from ingesting natural cannabinoids? People smoke both, granted. But the damage from injecting something that oftentimes has substances in it that literally tears apart your insides is kind of substantial, and the great majority of opiate/opiod addicts will eventually inject if they're not stopped; next to no one injects cannabinoids. How many people do you think assult their veins, circulatory system, limbs, or otherwise "parts" by injecting something with opiate/opioid activity? I just remember reading about someone who injected himself with water from a mud puddle because he was going through unbelievable pain and NEEDED his fix as soon as possible. Insufflating is also a physical issue, though much less serious.
You're not even right anyways, because opiates/opioids can depress breathing so much as to deprive the brain of oxygen, causing,(wait for it)... physical damage

. Oh lordy. Ever heard of marijuana doing that? Shall we get into the anti-carcinogenic aspects of marijuana?
Actually, alcohol can be safely ingested every day (in moderate amounts) by a majority of the population without them becoming emotionally fused to it. Medicinally, it facilitates social discourse VERY well, so contributes to the cohesiveness of our society, from helping people to their first lay to subtly breaking the ice when an old man meets his daughter's husband. It won't make you withdraw and worship the heroin deity. It usually takes effort and some other problem to become addicted. It is not a drug of the degenerate.
Actually, you know what Serotonin101, you be the judge. Here:
http://drugwarfacts.org/cms/?q=node/28. Which tower is bigger? Which might cause more overall damage? Quiz will be graded and returned next week.
Heroin is, to be honest, remarkably useless with morphine around. Marijuana and other chemicals have pain-killing qualities that could rival, too.
Anyways, I didn't even mean to quote you, but that was some warped stuff dude. You're going to put some fourteen year old kid on the wrong path with that shit. Fourteen year old kid, if you're listening, listen to me: weed is one of the safest drugs you can use recreationally, but it can still hurt you a lot if you disrespect it. Heroin is NOT safe to use. Weed is a treat if you choose and are responsible, but heroin becomes another food.
Ok...
I just wanted to say that the conversation quoted by the OP shows how bureaucratic the drug war still is. Even today, with the trove of evidence we have citing marijuana's relative safety, the DEA seems to be pursuing a policy largely based on 1940's hearsay. Its good that this person was caught in the act; maybe the powers that would take away liberty will realize, with enough such embarrassments, that they can't hide the truth anymore, and that a reasonable integration of now many illegal drugs into mainstream society could lead to the public good, not anarchy or what not. No doubt there is a lot of money to be made for a few in keeping many drugs sold by prescription or banned. However, I don't quite know all the facts, so can't make an absolute judgement.
Peace