wellyrn
More potent weed isn't more dangerous. No street drugs are really dangerous except for the quality and posible misuse.
There are two kinds of addiction - Mental and Physical. While THC isn't shown to be physically addictive, mental addiction invariably rises with the intensity of the 'high'.
Most heroin overdoses are caused because of the variance in potency on the streets. A user takes a regular dose that turns out to be twice as pure and OD's accidentally. Even in this dangerous and unregulated setting heroin kills far less people than prescription drugs or alcohol.
Heroine started out originally a regular sedative used during operations and such, I think it was around 1900. But it was soon abolished after patients showed themselves to become very quickly addicted to the drug. The only drug that has comparable addiciton levels as heroine is nicotine, but of course it depends on how you compare the two - if you were to inject the level of nicotine you have in a cigarette directly into your blood you'd die instantly. But the addiction on heroine is physical and withdrawal symptoms are some of the worst out there. On the other hand, Cocaine so far hasn't shown to be physically addictive at all. But the danger of Cocaine lies in that it allows you to cross your own physical boundaries, and your lifestyle can come to depend on that.
With pot the damage caused by smoke inhalation and various chemicals(pesticides, fertilizers,...) is worse than the effects of THC. I don't think anyone has shown any negative effects of THC itself besides temporary memory and motor impairment.
The most dangerous effect of THC physically is the chance of having a psychosis, which can be so severe that you can end up in a mental hospital for a while. The chances aren't big however, and it's not certain if the THC itself is responsible, or the impurity of the product. Still, too much THC and combining it with other drugs such as alcohol can lead to a bad trip, and I know people who are examples of this, and witnessed one first hand.
So care should be taken and more needs to be investigated. But compared to alcohol and nicotine, THC seems a fairly safe drug. Still, research is good. For instance research on how THC moves in your body. It doesn't stay in your brain very long (a few hours at most), but eventually it ends up in your cellular fats and it can stay there for weeks. I have no idea if this is possible, but say that someone is a regular user of THC, THC builds up in your body fats, and then this person suddenly decides to lose weight or start endurance sports or whatever. THC might get back into your body unnoticed. Still no immediate danger there, but say that you're not aware of it and you go driving, it might impare your judgment and you might get into an accident.
With proper regulation drugs would be far less dangerous and available than they are now. Soft drugs should be unregulated while synthesized drugs should be available through pharmacies.
I certainly agree with that. It is far more important that people know what they are doing when taking drugs, than just making them blindly illegal. We have enough empirical data to see that a 'War on Drugs' doesn't do much good. But regulation comes in different forms, and I think all drugs should be regulated to a certain extent. I'm fairly happy with how it works over here.
(seriously.) Only instant coffee sometimes has less caffeine than strong tea. In most countries, tea will have about half the caffeine of coffee. 
