I agree with your meaning of awkwardness. I, myself, have had those moments. However, you need not always use commas, and hence, the faster pace. I further conjecture that the writer intended the character of Leonardo to be a quick talker, the idea of commas omitted would not be surprising. He does show some agression in the story line. However, what you say is correct in the english language. But we must remember, that writing informally is prone to errors in grammar and punctuation.