interesting, how do they determine the fail in the first test? do they go by a set limit and anyone over is classified as fail?
A ratio of over 6:1 used to be a fail. They lowered the limit to 4:1. Don't know
if that by itself is a fail nowadays but the isotope test will tell if the test is synthetic.
Still leaves a bit of room to play as the normal ratio is 1:1. Guys were even adding
synthetic epitest to improve the ratio. I think they look at the messenger hormones
too which you mentioned (lh) if something looks suspicious. Doping with steroids successfully
isn't as easy as some think nowadays - if they really look closely at your samples.
Masking or substituting a fake sample is another way but must be complicated. Some Russians failed because their urine didn't have the right DNA. Testers became suspicious because
these athletes were too compliant with the testers! Always there willing to be tested.
If they REALLY look at your samples using all available science then doping with steroids is very hard IMO. If it were easy then the females for example would be matching/beating old DDR records but they aren't.