I might be able to understand a self-updating list of banned substances that says that anything like these on the list are also banned

This is such a list. The drug in question, while just developed last October, and while not specifically on the IOC's list of banned substances by name, was covered under the "thou shalt not use hemoglobin-enhancing drugs" clause of the IOC's drug list.

I still don't accept issuing a list and then not following it

It was followed.

especially in the case of the Spanish skier who got to keep 2 golds and lost one (does anyone think he got on the drug after the first 2 golds?)

AIUI, Olympic athletes are tested after every event. What they're effectively saying here is that said skier passed 2 drug tests and then failed the third. So, since he was clean, there's no tarnish on those.

Does anyone thing he got on the drug after the first 2? Entirely possible. Maybe he figured that the enhanced hemoglobin levels in question wouldn't show up "so soon" on his third dip. Maybe he got cocky, and figured he could beat the system. Maybe he got tired from the altitude and thought he needed the drugs. Who knows?

Maybe he was clean and got a bad drug test.