Too many people are content to believe what they read.
I'm more of a cynic with experimental tendencies, which allows for many more possibilities when it comes to these types of things.
Go to this page:
A good rule-of-thumb is that 90% of what is written and 99% of what is said is either poorly informed or downright wrong. I get kids in every day telling me with full conviction that the crap they've read in books is correct, despite any proof that I can offer.
Oh, and for those that are ignorant to the fact, the third highest strain of cannabis ever tested by a lab was an Alaskan Ruderalis hybrid that came in at nearly 36% THC. Not too bad in my opinion.
No one person knows everything about growing, and that's the truth. It's only though our shared aggregate knowledge can we truly advance.