A case of never letting the source spoil a good story
Of course, this is a problem that generalises well beyond science. Over and again, you read comment pieces that purport to be responding to an earlier piece, but distort the earlier arguments, or miss out the most important ones: they count on it being inconvenient for you to check. There’s also an interesting difference between different media: most bloggers have no institutional credibility, so they must build it by linking transparently and allowing you to double-check their work easily.
But more than anything, because linking to sources is such an easy thing to do and the motivations for avoiding links are so dubious, I’ve detected myself using a new rule of thumb: if you don’t link to primary sources, I just don’t trust you.