The document isn't dense. I found it pretty straight-forward, actually. It isn't short, but unless you are a member of the "tl;dr" contingent, the gist is pretty easy to discern.
The trick is that things like "Count one charged Auernheimer with conspiracy to violate CFAA § 1030(a)(2)(C) and (c)(2)(B)(ii)" translate to "Count one charged Auernheimer for breaking a law" and things like "See Perez, 280 F.3d at 329; see also Rodriguez-Moreno, 526 U.S. at 281-82 (citing Hyde, 225 U.S. at 356-67)" are references that you don't need to resolve in order to understand.
It also helps if you can translate things like "It is far from clear that this Court has ever “adopted” this test. We have mentioned it only once." into "oh no you didn't".
I do think your second sentence is apropos, but in a different way than you intended. Corn syrup, while calorie rich, provides neither protein nor necessary vitamins and minerals. For that matter, reading summaries is often information poor, compared to the underlying material.
For legal documents, research studies, academic papers and the like the cognitive load associated with wading through the original usually by far outweighs the marginal return.
The caveat is, of course, that one must be careful with one's choice of summariser.
I encourage you to read court decisions, research studies, and academic papers. Many are clear, insightful, and educational. It's also true that many are not, but I'm astonished by the number of people who don't even try.
At the very least, it's hard to judge the summarizer without sometimes comparing summaries to the primary literature.
Similarly, there's a posting now titled "Finally, usable GCM cipher suites in SChannel" ( https://news.ycombinator.com/item?id=7574678 ). I don't know what a GCM cipher suite is, nor what SChannel is, nor why it's a relief that this has happened. The link itself is not insightful. While it expands GCM as "Galois/counter mode", that's meaningless to me.
BTW, in this case, 'weev' matches some 63 other HN posts, though several provide no more summarized context than this link text. (Eg, a couple of other posts directly to other legal documents, a story about visiting weev in prison, and a letter from weev while in prison.) A Google, Yahoo, and Bing search all return http://en.wikipedia.org/wiki/Weev as the first hit. Perhaps one of those can provide the background you're looking for?
But as long as you're willing to hit the "I believe" button a few times while reading a legal decision they actually don't take too long to get the gist of.
Speed of dissemination definitely trumps ease of reading, so, yeah, I was wrong. The OP clearly should have linked to the source here.
http://arstechnica.com/tech-policy/2014/04/appeals-court-rev... is the first article.