I could tell you that I was being sarcastic, that coming up with their idea after reading it is called "retention" and not "invention." I won't, I'll just say "they found it first, and got dibs on it." Just like they would have dibs on the dollar bill they found on the sidewalk, which you would have found if they didn't. It's theirs. To do with as they wish.

Oh stop it. Of course I'm not confusing patents and copyright, I'm using whatcha m'call an analogy. Crime and Punishment is such an obvious novel that anyone could have written it. Especially after reading it. Much like you read the AsicBoost pdf.

It's imperfect, it's exploitable, but it's far better than nothing. Possibly due to the fact that inventors aren't a particularly powerful lobby, so the laws protecting their work are unlikely to be stacked in their favor.
As others have pointed out, this is all pointless rhetoric, since the Chinese (who'll most likely be making your next batch of silicon) don't particularly care about patent law & could release their next gen chips through some Belize corporation, perhaps with some catchy/original name, like AsicMiner.
So even if AsicBoost kids have the wherewithal to decap and conclusively prove, at gate level, that their patented methods are being used, good luck to them finding an entity to sue.