People who bitch about trolling might as well bitch about cold weather or inconsiderate drivers. Yeah, it's not always fun, but it is just the way things are and will be. You can't remove the human factor.

Disagree. Karma systems actually do that quite well, or at least have to potential to. Humans are like clay, and mold themselves to their environment. If you have an environment where there are no repercussions for bad behavior, you can expect such bad behavior. (read the recent NYT article on Steven Pinker, and how he was an anarchist until he saw how quickly people start looting when the police and firefighters went on strike)

So you can remove the human factor?

I don't know what "the human factor" is. Or maybe I should say, I don't think there is a single "human factor". Humans in a first world, upper middle class neighborhood coffeeshop behave very differently than humans in 1994 Rwanda, or the humans in the Stanford Prison Experiment. It's not that the humans themselves are different (or started out different), it's that the environment in one place encourages a different sort of behavior than the environment in another place. (I guess you could say I tend to favor Situationism over Dispositionism)

So, as a corollary, ideally you'd design the environment so that humans adapt to it in a particular way, thus getting rid of the 'human factor', whatever it is.

Well, getting rid of the sides of that human factor that we collectively wish to suppress. You can do it algorithmically with things like karma systems, but it's really nothing new, it's just a higher-tech way of doing what Hammurabi (and others before him) did.

That's not really true. In tight knit online communities it is very easy if not completely effortless to ban trolls. There are various ways to handle trolls and they all have value, as trolling is often purely a negative thing.