I think a mirror are worth packing in a kit.
When using a mirror, think of it as a rifle with front and rear sites. That mesh is the front site and the circle is the rear site.
Now that mesh is actually a tiny irregular mirror in itself laid out in a grid or mesh. The sun shines on that mesh and since there is no set pattern to the mesh, the mesh is able to collect light from almost any angle the sun is shining from in relation to you, and create that little ball of light. The only reason it is a mesh is because you have to be able to see through it or you would never know where that ball of light is to line things up.
Now the mesh is the front site and you have your ball of light in it. Now you need to line up the ball of light or front site, and place it in the circle, then place the ball of light on your target. You just turn the mirror until that light moves and lines up on your target and you are done.
As you are moving that ball of light, what is happening is different parts of the mesh are lining up with the sun and making the ball of light appear to be moving across the mesh. While you are doing that, the large surface of the mirror is also moving in the same direction towards your target.
Not the best explaination about the mesh, but it is the best I can do without actually being one on one.
As far as using two mirrors, you would have to have the sun to your back and your target to your front. Basically 180 degrees apart. Think of it like a football field. The sun is in one endzone, the target is in the other and you are at the 50 yard line. You could use two mirrors at that point, but really, if you think about it, your target is going to be looking right at the sun trying to find you. Even if the target was doing that, do you think that little mirror will out shine the sun? At that point you need to create an angle between the sun and target.
