Somebody getting caught is not a proof of the system working. I mean, cycling had plenty of people getting caught for steroids in the mid-90s, but the majority of the riders were pumped full of EPO.

20 games? That's like, what, 3 months of suspension in the NHL? That's peanuts compared to what you get in pretty much any other Olympic sport - minimum WADA penalty is 2 years. The testing regime is also a joke - there's team-wide tests once during the training camp and once in the regular season. That means once that team-wide testing has been conducted, you're pretty much free to do whatever you want before the season ends and the off-season is completely non-supervised.

As for the individual testing, a maximum of 60 players get individually tested in the off-season - meaning the chances of getting individually tested in the off-season are extremely low and even if you do get picked, you have two weeks to respond and show up for the test. There's also no testing on game days, meaning that every single player could take plenty of doping on the night before a double header, because 3 days is a long time to clear out your system.

The system is utter shit and in my mind 4 suspensions in the 10+ years the policy has been in effect is proof of it. If it wasn't for the recent 3 suspensions, that would look even more suspect, don't you think?

As far as I remember, all of them claimed they were unaware what they were taking contained/were items that were banned.

Well, yeah, but since we don't know any details, what else would they say? If they get caught for using bog standard steroids that everyone know are banned or, say, synthetic EPO that just doesn't enter your blood without needles and shit, it would be much harder to make that claim. Without details being released, it's very easy.

Besides, ignorance absolutely is not an excuse.