What he's saying is that clean room reimplementations (Dalvik) side-step copyrights, but not patents. The fact that it was created to circumvent something, just not this particular thing, could lead to a lot of confusion for a lot of less savvy readers if this wasn't cleared up.
But your second point is valid, and I agree that some things needed clearing up. I just thought the way that particular comment was worded wasn't helping that much.
Going back to my Russian roulette analogy, of course playing Russian roulette won't protect you from getting shot. It's the fact that you're playing Russian roulette in the first place that is putting you at risk of being shot. If people are confused about that, then it's probably best to educate them about how playing Russian roulette can result in you getting shot.
Bringing the analogy back, I feel like it would have been more useful to just educate people about the fact that creating Dalvik is what directly led to this suit and for what reasons.
While many people think that Dalvik was built to protect against all kinds of lawsuits, this is not true - it only protects against one kind - copyright/tradesecret lawsuit, and does not protect against patent lawsuit. This is exactly what article says where you quoted it. The reason why it needs to be pointed out is that, well, many people do not realize the difference.
Does it make more sense now?
My point is just that it's a little weird to say that Dalvik couldn't protect Google from a patent suit, because building it created the suit. It's a little like saying that playing Russian roulette can't protect you from getting shot.
But I've belabored this point enough I think.