I don’t think I have ever been in a Greek class — either as a student or a teacher — in which punctuation was discussed as a tool for translation. We look at case and tenses and the meanings of words, but not how punctuation can help convey the meaning of the passage.
This is not a good thing. Because Greek uses endings (for the most part) to convey the relationships among words, Greek can insert words and even phrases between two related words (or phrases). English, on the other hand, uses word order and proximity to indicate relationships. In the sentence, “The black cat chased the little mouse,” we know the cat is black and the mouse is little because “black” is close to “cat” and “little” is close to “mouse.” But this does not work in Greek.