Also the way Conor make outline is not good. Model will have twice more polygons
the shading method is a applicable still and would give the needed cell shaded look althogh the shadowing is defiantly not acurate the the lighting in terms of light direction and afaik the model would not respond the light colour. perhaps allowing the normal lighting then applying the shading method after would still give enough of a 2 tone look while also allowing for smoother lighting underneath
also on the codehunters video i noticed some black outlines built into the textures of the models but none around the edge. conors method of character shading is a great for this as it allows a detailed character texture and still get the nice lighting 2 tone lighting
warsow had some pretty nice looking levels but they used the same mothod as conor to get the outlines and did increse the pollys a bit and also since you end up getting black outlines agaisnt stnadart gemetary bad effects can ocour. i think if you do take the method, include the polly offset shader command in you black outlines texture