The page contains a full description of the Hyperloop and a link to a PDF with technical details.
You're linking to your own HN story, which has fewer comments, and fewer details in the actual story. (Also, why not link directly to the _actual_ news story @ Businessweek as you mention?)
By the time I've posted both the Businessweek link and the comment the SpaceX.com page was a mere placeholder. A few minutes later their site cache cleared.
Context is everything. ;)
In any case, I've deleted the comment you were referring as it's not relevant anymore.
You're linking to your own HN story, which has fewer comments, and fewer details in the actual story. (Also, why not link directly to the _actual_ news story @ Businessweek as you mention?)