I was fortunate enough to discover The Complete Walker early on, but I recall lots of bad advice, mostly from salespeople and Backpacker magazine.

I recall one salesperson, extolling the virtues of the Kelty D4 (old version), assuring me that if I used a pack made of coated material my food would smell like my dirty socks.

But it still goes on...Just recently, I overheard a salesperson at REI telling a customer that you must absolutely wear wool socks when backpacking, never synthetics.

Most of this backpacking "wisdom" is just someone repeating what they've heard or read somewhere, and the internet has exacerbated the problem.

The best advice, which I later passed on to the lady at REI, is to take anything anyone tells you with a grain of salt.
Always remember that you are absolutely unique, just like everybody else. -Margaret Mead