DIsplace Modifier Problem https://gph.is/2QKbRBK
I'm attempting to use the displace modifier to cause the desired effect as shown in the gif, but the issue is that the modifier's strength is limited by the placement of the highly subdivided edge. 
The mesh is in a vertex group called "displaced" set to weight of zero with only the highly subdivided edge set to a value of one. This allows just that edge to be displaced in only the x direction.
Is there any way I can get the blue to fill in where it overlaps to the red side?

other details:
The UV map is simply a square divided in half with two colors. The highly divided edge is right over the line between the two colors in the UV editor. Changing the location of the object's origin has no effect. The displacement is governed by an animated empty object. All texture settings result in the same problem, only strength of the modifier can be lowered to get around the limit but is not a desirable effect.

I bet somebody has a cleverer idea of how to achieve my goal, and I'd like to hear it.



Other problem is that rendered view shows a blend of the colors. 
https://gph.is/2NXizGb
My original UV image had a middle stripe of a blend of the two colored sides creating an illusion of two colors mixing in Blender. 
I recreated the UV image with no stripe. It's working now. Also, I recreated a plane mesh, and instead of subdividing it a lot as I had originally tried, I used a ton of loop cuts in the axis of distortion (y), and then another loop cut perpendicular to that (x) and marked as seam to bisect the plane.

https://gph.is/2Dh8vDE