I've been on the site a handful of times and usually don't comment. How it works for me is just like a newspaper -- if I'm not hooked by the first few lines of the first post, I don't typically read further. Something to realize is that a "view" doesn't necessarily mean that the entire thread (or any of it, for that matter) was read -- just merely that the title-link was clicked. What with the ever-limited time of people these days, I suspect that there are others who only get as far as the first few lines before moving on, but this is just a guess...
One more thing that I've noticed here in the forum are some abrasive and/or sarcastic comments -- those hinder community participation rather than invite it, IMHO. I'm not complaining -- that's free speech, right? But still, if there's a chance to get flamed or treated with sarcasm, many people will not participate.
Just wanted to demystify at least a couple of reasons that people may not be commenting -- these have been mine.
Hope to see the Pipeline continue to grow!