Looks like they took a page from Cor-Bon with the "Power Ball".
Richard
PS: After checking out their video I am of the opinion that this is the ammo designed specificly for the LCP.
No doubt it is the LCP ammo. As to the Power Ball analogy, kinda sorta. The flex tip material Hornady is using fills the entire hollow, and is actually compressed down and bulges at the sides as it does. So the flex material starts the bullet expansion by it's own deformation properties under hydrostatic pressure. Think of it as a gooey eraser. Squeeze it top and bottom and it bulges out.
Powr Ball has a hard polymer ball sitting on top of a conical hollow, and it starts expansion more on a lever principle. Ball goes down, cone moves outward.