I have a wall in the middle of my house which I have been told is a shear wall.  The image below is a diagram I put together real quick to show what it looks like.  The grey lines on the right are perpendicular exterior walls.  The orange-ish section on the right is actually exterior since the foundation jogs a bit there.
![enter image description here][1]

It doesn't seem like the 1x6 that crosses in the middle does much.  I intend to put French Doors in this wall but need to know what I'm getting myself into.  


  [1]: https://i.sstatic.net/09dOZ.png