Heh you're kinda assuming some things about me here. I do have sexist friends. Not many, but a couple. I keep them around because ignoring them means they go on being sexist. We have occasional debates about it, but more importantly they see the unfair things I struggle with. Even if we never see eye to eye, we learn from each other. If it gets to the point where knowing them is bad for me I'll happily cut them off, no problem. But for now, my goal is sharing and expanding each others worldview. To me, hubski seemed kinda about that too. I'm not blaming hubski, although I do believe grendel is proof that the site probably has some kinks to work out. It's hard to invite my friends to the site. "Hey check out hubski! It's different from reddit! Women are welcome!"
"Um.. rinx... why is the 3rd post down about whipping feminists" "Oh trolls are a very small minority, you can block them!" "yeah... that's what people said about reddit" For me personally he doesn't bother me. Like I said, I know people like him in person. Once you've met them it's impossible not to feel sorry for them. I would like to see him have less representation in #feminism, so that's why I suggested us consolidating on a tag to filter.
I think the difference is though, that while you and your friends disagree sometimes, you can still have civil conversations and healthy dialogues. My best friend and I for example, we agree on almost nothing, but that doesn't get in the way of our friendship because we have an honest respect for each other's opinions. With trolls, it's a different story. They often choose belligerence for the sake of belligerence and when you discover that they're not there to be reasonable, sooner or later you have to decide how far you really want to go to work with them.
Sure, my point is more, I'll always start with an attempt at real conversation. If it's obvious I'm talking to a troll, or it's something that is unhealthy for me, I end it. Otherwise I try to keep the pipeline open even if I disagree with people. Grendel's an obvious troll, but probably also a really unhappy person. I don't regret at least attempting a reasonable conversation, although I won't keep doing it.