It was abused for spamming.

Edit

Can't find the discussion anymore, but deactivation caused problems for choroba's CB client.

No, we had an open relay, which is not a redirect page that requires user to click proceed to proceed outside of perlmonks.

if url is no longer in whitelist throw up a redirector page?

search box link shortcuts like doc:// redirect to perlmonks.org, Keep getting 'Permission Denied' when try to post, Re^4: Post within CGI

Semantics, it has been called link-redirector before, also by the gods.

And the concept is close, it could be reactivated and extended to show the warning you are suggesting, if the gods wanted to.

(I'd say only warning if a domain is not whitelisted, to cause minimal disruption)

BUT since the monastery also allows <a tags, all nodes would need to be parsed and the links updated for this.

edit

The other aspect worth discussing is if an intermediate page would really demotivate spammers and SEOptimizers. The final link might need to be hidden behind JS... (headaches)

Cheers Rolf
_{(addicted to the 𐍀𐌴𐍂𐌻 Programming Language :)
Wikisyntax for the Monastery}