yeah this is completely true -- you have to talk and sometimes just drop coding completely in order to explain concepts etc. to your audience. I think this is a great skill that can be applied at your IRL job as well -- have gained a lot of confidence since i've started streaming.
Correct... A major part of streams is the community you build, not the content. Some people get away with just pure content on twitch but usually they're either really great artists and the process is just beautiful to watch or they're pro gamers who people watch to pick up top strats even if they're not engaging otherwise.
Just talk your mouth off, seriously. It's the best tip I can give you to make it interactive.
You gonna open a file and do something, say it, don't just do it. When you are thinking of a problem, ask for suggestions from the crowd/viewers...
Also, ProTip. Vim is a problem if you navigate really quickly along splits (like you should), people lose focus and will just stop following.
I switched to Atom for my last stream (I hate every minute of it) but it slows me down enough so people can follow better.
Hope this helps