Prior to shaka, african conflicts was rather "peaceful" with the tribes rather intimidating each other with the sizes of their armies. Shaka revolutionized the zulu fighting style, so to say its always been like this is false. Shaka saw the power of this european tribe but thought he could build a stronger zulu tribe. He then conquered the other smaller tribes for the previous reason aswell as the fight for ground became more intense. The tribes grew because of the introduction of some european vegtables etc.
As for the hutu thing, they are actually from the same race, but the european rulers declaring one group superior to the other based on their looks. When the europeans left, they left a smaller privaledged group and a larger disadvantaged group. (Sounds fimiliar?). To "solve" the the equality problem, they just took out the the minority to make every one equal.
And the rest is history. Africa as a continent were more peaceful, that's why they are technologically behind the other continents in my opinion - conflict forces progress.
Now my opinion on the topic - apartheid almost always plays a part in things that happen in south africa, but to say it played a bigger part than the incompetance of the government is going to far (I didn't read the article so I don't know that is what they claimed). Apartheid will always be a secondary etc. reason and can't be seen as a primary reason anymore.