I usually only read comments relating to HN "on-site" content such as "Ask HN". I also tend to up-vote these more than off-site content. This is probably due

I usually only read comments relating to HN "on-site" content such as "Ask HN". I also tend to up-vote these more than off-site content. This is probably due to the fact that I open all the interesting links in tabs and then move off HN to read them.