Do add shaders increase rendertimes?

I was watching CynicatPro’s Ubershader tutorial and he said that mix shaders apparently increase render time.

First, is this true?

If it is, I found a way to mix shaders with an add shader and weight them with the color shader inputs. So my question is do add shaders increase render time?

Having more BSDFs will always increase rendertime, no matter how you combine them.

Moved from “General Forums > Blender and CG Discussions” to “Support > Materials and Textures”

Add shaders will more than likely add excess energy to your scene, and therefore it’s incredibly easy to create shaders that will never converge.