The rule is, if you come from Google, the answer is hidden at the bottom of the page, behind a bunch of things that say you need to sign in. But if you don't come from Google, the answer is hidden unless you're a member, so you can't e-mail the URL with an answer around to pals, for example. It's a similar policy that the WSJ has for articles, built to keep the Google benefit while encouraging subscriptions.
They used to have a better paywall where Google's spider could see the results to index but if you went there - even from Google's cache you couldn't.
I suspect Google cracked down on this so they had to unblock the results. The block is in place for a few scientific journals, they must have worked out some deal with google to protect their content.
The rule is, if you come from Google, the answer is hidden at the bottom of the page, behind a bunch of things that say you need to sign in. But if you don't come from Google, the answer is hidden unless you're a member, so you can't e-mail the URL with an answer around to pals, for example. It's a similar policy that the WSJ has for articles, built to keep the Google benefit while encouraging subscriptions.