Being in my first season in DIII I have a better idea about how some of these D.IV teams can go so far in the cup. If you have a promotion worthy team in D.IV you can TIE against just about everybody in your league and even rest your starters during league games so they are in top game shape for Cup games. I doubt I make it in the as far in the cup this year as I have the past 3 years (while I was in D.IV). Mostly because I need to focus more of the effort and enthusiasm on league games rather than cup games.
Even so, I'm not complaining

as D.III is where I want to be (for now)