My hypothesis is that reading English (or native-language) classic literature helps with learning classical Greek. When I was in high-school and college I avoided reading the "classics" as much as possible because they were boring. Instead I read a lot of sci-fi and fantasy. But in the last few years I've turned back to some of the classics and I can't help but notice how the language structure in those books (e.g. Swift, Melville) is much more Greekish than what I find in modern fiction. For example, classical English literature makes much more elaborate use of participles than much modern writing. I find that this helps me. Now when I see complex participle phrases or uses of relative pronouns I relate them to Greek which makes the Greek grammar seem more natural.
Maybe it's just my particular experiences (or lack of experiences...) that leads me to see this correlation but I can't help but wonder if a person who is used to reading more sophisticated native-language literature might do better while learning Greek than someone who has only focused on less sophisticated stuff.
Has anyone else noticed this?