Oh that's troublesome then.
For example, I've always ranked Lifehacker on my bullshit detector as far as bad "research due to quantity" blogs go.
I also don't have respect for IGN and Gamespot and I only tolerate Gamefaqs because I know no other.
However they're not only the authority in their category because of their consistency but you have to join a community to find out what the true quality sites for each category are and the only other guaranteed way to make up for that is to be a slot junkie who treats Stumbleupon like a game of slots.
In real life or things like authorship, the same problem rears it's head again.
You can go look for sources but then you'd not only have to take longer to digest something but your subject needs to be of the verifiable kind and not something more case by case like say friendship, relationship, howtoes, manuals and such.
Even with heuristics, you have to assume you're the one holding the cards. Guys like me who don't know about many subjects like say... programming are going to be suckers for books on say... O'Reilly and only realize not all of them satisfies us or are good enough without follow-up books.
Similarly with strangers, it's like meeting a guy in a gym and you having never worked out before and not having money to pay a trainer. How do you not get goaded into that guy's training regimen especially if you're shy or such a weakling that light plates look heavy or looking good = strength training and you're just desperate? (Even with trainers, how do you judge without that experience and when you can't experiment between trainers?)
It is an interesting topic though but I don't have an answer. My only heuristic is to never give up. Never stop clawing at what I don't know nor give up totally when I feel like quitting on verification because I just don't have a map to refer to.