Oh, aye, if one wishes to be able to speak Japanese well, other people are pretty much a must, I expect, and conversing in Japanese (or attempting to do so) can certainly a powerful tool for learning the language in general. But not everyone has the time/people/other necessary to do this a lot.
And AJATT doesn't ignore people alltogether. :] The blog's author spent time with Japanese speakers too (what his area's number of Japanese speakers allowed, anyway). His blog just describes a way of learning that has been effective for many. It may not be for you, but hey, we're all different.
So yeah, learning with people, or by being with people who know the language already, can't be ignored. But that blog doesn't ignore it either. And if you want to be able to read and write (which is what I'm working on atm), you can't ignore everything other than people either.
Myself, I can't just magically find a Japanese person (and probably won't non-magically either) and become fluent, so I'm aiming for reading and writing (with pronunciation when I start studying sentences) for now. Once I'm no longer useless in that area, well, there will be even less Japanese in this area, as the university is probably losing Japanese as a subject next year. :[
So yeah, the internet is nice. :]

TL;DR: Yup, people are nice. But don't ignore the rest. And AJATT doesn't ignore either part, so all's well. And people learn well in different ways. And Trondheim lacks Japanese people. Meh. And also, the internet is cool. Yay. :]

Hm. I like that tl;dr. Just go ahead and read that instead of the rest. :] (So I tell you at the end, eh? What a bastard I am.) [EDIT: I bolded it so you'll read only that anyway, 'cause I'm a nice guy after all. Why don't I place it first you say? What's that? I can't hear you over the sound of the typing of my silly footnotes.)]