I think the danger depends on the level, condition, training backround etc of each person and how he uses it, and not exactly on each training technique it self.
As MaB said, "I believe high intensity work is dangerous for beginners...", it is not necessary the high intensity technique thats dangerous, but the level etc of the beginner etc, because he is not able to handle this kind of techniques etc.
But there always exceptions for anything.
I agree with this above, but I don't agree with the explosive work for older lifters etc.
I think it is a matter how someone uses something and what training base someone has or achieved etc, and I believe with explosive work the danger (if there is any, with bad using etc) is the same at every age.
Too many "etc" in my post, but I think you get my point