Scott Cosby is a friend I've known professionally through his work as VP of Products and Operations at Invincea. I recently watched a video which featured Scott demonstrating a typical Spear Phishing attack and how Invincea mitigates that challenge.
Invincea cannot prevent attacks, in fact, it was produced with an understanding that crafty bad guys will always find new ways to attack. But it can rapidly detect that something is wrong and mitigate attacks, even when you have users doing things like clicking on links they are not supposed to. The video below highlights this fact well. You will see what happens when a user clicks on a link that looks valid and how Invincea responds.
The video is pasted below for your reference.