The linked article goes into detail about what I mean about that, but what I mean is that some of these concepts have a lot of mystery around them that are not

The linked article goes into detail about what I mean about that, but what I mean is that some of these concepts have a lot of mystery around them that are not deserved. Many people penetrate this mystery and then wonder what the deal was with the mystery. For these particular concepts, that's generally a good sign. Iterators are important... but they are not conceptually complicated. They're just a way of getting a "next element". Behind that may be a lot of complexity for some particular iterator, but that complexity should be accounted to the implementation, not the concept of iterator.