I believe Rippitoe wrote some rational things that beginners and naturals to follow.
When I started BB'ing, I followed Rippitoe, Bill Starr's and then Stuart McRobert's methods/ philosophies - regardless of how they looked like. I think that gave me some good foundation but I am naturally not a strong/ powerlifting type. And as you gets more advanced, you just need to tries out what works for you and what not.
Regarding lean guy becoming fat blob, Dante (DoggCrapp) once said that the only way to become big naturally in quickest way is first become a big fat slob, then slowly stripped off the fat. Slowly - being the key word here.