Im not a military guy (in the sense of bravely risking life and limb for country in the field) and have never taken steroids so maybe I shouldnt post here, but I do have experience with being tested by Defence Dept doctors for steroids (albeit as a civilian, and it was the Australian Defence dept not US) so I will post.
Basically when I got a job as a defence scientist with the Australian defence dept (since left to do a PhD) soon after getting the job I had to do a standard medical exam (not sure why, health insurance and to make sure I wouldnt drop dead on the job or something) and after weighing me the doctor was shocked and couldn?t believe how much I weighed (around 230lb at the time) I guess I must look a lot smaller with clothes on or something.
He then made me take off my shirt and flex like a body builder (to prove it was muscle not fat). He then asked me several times (he just kept at it) did I do steroids and I kept emphatically saying no but he didnt seem to believe me. I said to him you can take a blood test and test me for them if you like (I didnt expect him to actually take me up on the offer).
Anyway he did take some blood from me though I didn?t know it was for steroids at the time. A couple of months latter the administration/pay woman at my laboratory informs me that I?m not doing steroids. I said yes I know that. She said theyd tested me for steroids and the test had come back negative. She then tried to convince me that there must be something wrong with me (my muscles too big or something) if they were testing me for steroids.
At the end of the day it sure made me feel good though, you know youre doing something right if they assume youre doing steroids when your not (better I guess than people assuming you not doing them when you are).
Moral of the story is if they test suspicious looking defence civilians they may indeed test suspicious looking uniformed personal (at least that seems to be the case with the Aussie defence dept).
(On a side note I didn't get the health insurance as my BMI was way too high, Im 5'9'. The doctor reckoned no other health insurance company would touch me either now that there was a record in the system of me being at that weight. I haven't tested that out by applying for it but thats OK the default public health insurance here unlike the US is pretty good).