How does it work?
There is a well-known trick that if you want to read a WSJ article, you just search the title in Google and click through there. This extension automates the process by making your browser pretend that all your links to wsj.com came from Google.
Is this moral?
It's exactly the same as the Google trick. If you're ok with that, use this extension to save time. If you think that's wrong, then don't use this extension.
Does it work for other websites?
Not right now. WSJ WallJump was made in about 15 minutes to solve a problem. If you want to suggest another website where you know the 'Google trick' works, use the Contact form.