I have read this entire thread twice with great interest and a lot of thought. I am a true "natural" athlete. I have taken and passed urinalysis and polygraph tests in shows run by the NGA, OCB, IDFA (Canada), WNSO (Canada) and SNBF. I have also competed in five NPC non-tested shows. I have competed in a total of 16 competitions and have won 32 open weight, height, age class and Best Poser (3) trophies. Nine of my trophies are from the NPC. In addition to a World Championship in my age class, I hold two natural Master Pro cards, one from the US and one in Canada.
There is no doubt that you find heavy steroid use in the NPC. If you are going to play with the big boys and try for the IFBB, you have no choice but to juice or use gear.
In the natural competitions, you do have a choice. Yes, some athletes chose to take banned drugs and compete against those who don't. Maybe it's because they are not good enough to win an Open or even their weight class in an NPC show and want that title so badly that they give themselves an edge. It's a matter of character. The testing in the natural arena is not that good. You can pass a polygraph test without too much trouble, if you want to. The questions is, why would you? Is cheating worth a $25 trophy and the knowledge that you were the best that night because you enhanced yourself with banned substances? Character!
Urinalysis tests do not detect Growth Hormones. So if you do GH and are given a pee test, it's no big deal. However, if you say you aren't on GH, when that question is asked, you just might fail the Poly.
Urinalysis picks up most of the banned substances, but sometimes, a promoter won't even submit the samples, because it costs them money and if the show didn't do that well, they might look for a cost cutter.
In reality, the Poly and Urinalysis test is a gut check. They try to weed out the cheater by scaring him or her away. Most of the time it works. Most users are more interested in competing in the NPC anyway, that's why they are on the stuff in the first place.
The whole natural bodybuilding scene came about because many athletes didn't want to take steroids, test boost, Andros, diuretics, or Growth Hormones, so the natural contest was born. The NGA, OCB, INBA, INBF, SNBF, NPA and IDFA (Canada) all try to run clean shows. Unfortunately, some of the athletes who compete are not clean. Again, it's a matter of conscience and character. If you want to compete as a natural athlete, you need to be five years drug-free (a few federations call for seven years).
The testing is getting better, while at the same time, some athletes are getting better at beating the system...for a $25 trophy and an ego shot. But, in their heart....they know.