Drawing wireframe single pass , switch on off

Hello everyone !
My name is Marco Giordano and I am new on this forum.
I started studying opengl for a month or so and I was able to get some basic decent result, a 3D viewport with loading objs, basic lambert etc.
Now I wish to implement the single pass wireframe drawing as nvidia explains.
It looks quite simple to implement, but here comes my question.
What I would like to do is to turn on and off this effect in my shader pipeline, Problem is that in order to achieve this effect a geometry shader has to be put in place,
if I want to turn it “off” I will need to bypass the shader which will still have a small overhead or switch the shader (I read this is quite expensive to do so).
My question is what s the best way to achieve that switch with this particular tecnique?
Maybe is it better to stick to the old double render (solid + wireframe) technique?

Cheers

M.