The answer to that isn't a simple one and probably depends on the person. Everyone on HubPages is different. Every Hub is different.
Personally, I don't network at all. I do participate in the community, but that's as "social" as I ever get. Contrary to the suggestion that someone else made that people who get good scores "don't have a life" - wrong. I have a life - complete with kids (grown ones but important in my life nonetheless), other family, friends, social life (not a wild one, but nice enough), "real" work, house, yard - the whole bit.
It isn't necessarily a matter of people with high scores being the best writers. We can all see that's not the case. There's "a ton" of great writing by people with all kinds of different scores. Besides, what's "better writing" is often a very subjective thing. Also, the same person's writing can be better or worse on some Hubs than on others.
HubPages makes it very public information that what goes into the score is a mix of different things. It's not one, single, thing.
All I know is that I don't network at all, do have a nice, full, life; do participate in the community (more on the forums and in "Answers" than in any other way), and aim to produce good writing (even if it wouldn't be considered "the best writing").
Now, if you could excuse me... I need to go to my 879 social sites so that I can spread the word about the recent antics of my imaginary friend, "Ivan, the Purple-Striped Giraffe", who only shows up when I'm all by lonely self and trying desperately to figure out how I can keep my highest HubScore for the rest of my empty and hopeless life. (Ivan's kind of shy, you know. He won't come around if he thinks anyone else is here.)