Blood doping is curtailed right now because of the biological passport (there need to be way more tests for it to be truly effective, in my opinion, but at least the tools are already in place to severely limit the effects of blood doping without necessarily detecting any products in a test). It is my understanding that both Aicar and GW-50 are relatively easy to detect right now, but that might change with newer products. Some believe that kind of PED use might have replaced blood doping at the top of the peloton. My question would be: if at one point similar products couldn't be detected directly, would there be a conceivable way to curtail their use indirectly, like the biological passport does with blood doping?