Fellow comment discarder here. You wouldn't guess by some of the long-winded replies I've made across various sites but that's a big part of it I think. I often write comments as if I'm having a conversation in my head so there's not a clear structure like you'd find in an essay or "proper" written piece. Then I start thinking of all the ways someone could miss the point and end up rambling.
See? Almost doing it now.
