You can't control whether someone else wants to have a conversation.
I've been blogging for almost 6 years, now with 40,000 RSS subscribers. I can tell you I have 0% ability to predict which post will be popular, causing lots of retweets and comments, and which are duds. Not time of year, not topic, not how excited I am with the piece, not length.
What that means, to me, is that you write a lot of good stuff and the conversations increase overall, but post-to-post it's necessarily unknowable.
That's OK, that's just the medium.
That's how I'd pitch it.
