I don't the link's particular destination here matters too much. His main point pertains to the increase of clickthrough rates of (any) link by changing the language of and around its text.

I guess my point would be why, as a reader, would I want to follow anybody? Sorry for changing the point of view to the seller, but I'm wondering what's in it for the buyer? What's the transaction that's taking place here?

Given that piece of information, applying some of the practices of persuasion mentioned in other posts starts to make sense, but without understanding the transaction, I'm not sure what his point is. Just to get people to click a button? Surely there's more to it than that. (Although I _do_ get the A/B kind of discussion, just wanted to move the discussion towards a "what's in it for me" vein if I could)

EDIT: Instead of all this A/B crap, how about just honestly tell the reader why they want to do this? Is that such a crazy idea?

Dustin's research has applications in areas where every word makes a difference in your marketing efforts, or in guiding users more effortlessly through a process. That's why it's important.

Ask them questions. I've used Twitter for everything from finding good bars in Bristol to getting someone to take a photo of the front door to a cold war bunker (twitpicced to me within 20 mins of the request for a picture).