Fair enough... if that's coming from a small number of highly-ranked comments, that is indeed evidence that a lot of people are interested in the exchange. (If it's a large number of low-ranked comments, it's equally consistent with a small number of people who endorse your engagement in it.)
That seems like an accurate assessment. At present this comment http://lesswrong.com/lw/54u/bayesian_epistemology_vs_popper/3uqx is at +8 and this comment http://lesswrong.com/lw/54u/bayesian_epistemology_vs_popper/3usd is at +13 but the second comment also got linked to in a separate thread. No other comment of mine in that discussion has upvoted to more than 5. That data combined with your remark above suggests that your initial remark was correct.
My impression is that critiques of lesswrong mainstream positions and arguments for contrary positions are received well and achieve high karma scores when they are of very high quality. Similarly posts and comments that take lesswrong mainstream positions will still be voted down if they are of very low quality. But in between there seems to be a gulf: Moderately low quality mainstream comments will stay at 0 to -1 karma while contra-mainstream comments of (apparently) similar quality score solidly negative karma, moderately high quality mainstream comments achieve good positive karma while similar quality contra-mainstream comments stay at 0 to 2.
Do you share my impression? And if this is the case, should we try to do something about it?