Hansen himself admits to doing steroids in his book he wrote a few years back.
That right there says it all. There's nothing really special about the guy, really. It's hard to take anybody like him seriously when he's an admitted drug user (not for long, but once is often enough). All his training techniques mimic Arnold's training routines, more or less. That's the biggest sign right there: if he knew anything about training without steroids, he'd realize that drug-free guys can't train like that, on average, and make gains.
It's a shame to say but even Bill Pearl falls under this category. He's admitted to trying them, but won't admit to how much. No matter, if you've done it once, then you're a steroid user. Your credibility is therefore gone. You mean to tell me a drugged to the gills Arnold loses to a completely natural Bill Pearl way back when?...sorry Bill, I have a lot of respect for his physique but I have yet to meet a completely drug-free bodybuilder with an enviable physique...other than perhaps Steeve Reeves, but his genetics are obviously one in a million.