I am having a hard time understanding what he's complaining about. Is there supposed to be something wrong with having a general information site (mahalo) and a bunch of specialized sites (starwarsanswers.com, for example) that contain information on specific topics with links back to the general site?
What purpose does this serve? Maybe you could explain to me why someone would do this? What is the benefit of using several different domains instead of subdomains or subfolders on the general site?
A couple days later, Bob wants to go there to check out another Star Wars question. All Bob remembers is "starwars", and fails to find the site.
Compare to "Hey Bob! I found the answer to that Star Wars question we were discussing at lunch yesterday on this great site, starwarsanswers.com".
A couple days later, Bob wants to go there to check out another Star Wars question. Bob has a good chance of remembering "starwarsanswers".
Separate domains for different topics is more friendly to users. That's probably why Google has no problem with it--as the Google guy said, its impact on users they care about.