I'm not sure about the lack of self-control, as such. I think there is this, but only in certain senses. Feanor was a very self-controlled individual, except in two particular ways.
His oath is fascinating in its motivations, of which there were basically two:
1. what he loved
2. his separation
He loved his father, the silmarils, and his superiority/separation from other Eldar. While he had the first two, the effects of his separation from others was mitigated.
He lost his father and his silmarils in the same day, and Morgoth was responsible. Feanor was not in control of what he loved, nor of the degree to which he was separated from others by his abilities, his birth mother, and his character.
His separation from others combined with the loss of what he loved, resulted in anger and hate. The oath sprang from this. Why an oath, though? Why swear to his course of action? The reason was to demonstrate his determination to regain at least the silmarils, for he could not regain his father. He desired the silmarils and he was proud enough to believe himself capable of reclaiming them from Morgoth. The result was his passion, which took the form of the oath he and his seven sons swore.
So yes, there is an element of lack of self-control, but there is a lot of self-control in Feanor too. Considering how Feanor was described, it would take a lot more character to control oneself if one was Feanor than if one was, say, Elempí.
