Thus, to continue with IsaoShi's thought, you would Color_Add() the output of the Blinn node to the output of the diffuse() node before plugging into alt_diffuse or alt_specular... doesn't matter, they both do essentially the same thing.

This is easier to visualise in a node set (my apologies to GC converts for leaving out those essential bits):

This is not impossible to do using the diffuse_color and diffuse_value channels (we just saw BB do something like it in the Nylon Material thread) but it is simpler and you do have total control over your materials.

Of course, GC is missing here (feels weird to be putting this together without GC - like, what's the point???)

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

Metaphor of Chooks