But the realitiy is not like you mention it here. I worked with a lot of engines, indie and professional ones. And when I talked with the makers of the Vision3d engine about their documentation I learned, that they even split documentation into artist and programmers documentation, just because all their customers work that way. There are people responsible for different areas of a game. And only a few projects bring their own shader programmer. Many projects will not touch shaders at all and will rely on the delivered technology. That is by the way the reason why they spend so much money on an engine. They want ready-to-use technology. They want to save time and want to finish a game. It does not make much sense to finish the engine, especially in the today's market where you often have to make smaller games with a small budget.

Actually you are right, that it is very easy to make a normal mapping shader in many engines. There are visual shader editors in C4, Unity (as a third party plugin), in Vision3d and in UDK. So it is just connecting a couple of nodes in the right order. But later it might be harder if you desire to let them interact with light-maps or directional lightmaps or other effects. Some engines have all that integrated into the nodes, others need some manual work, especially when you have a cross-platform project.

So it is not always a big problem. Often artists can do it on their own. But when it really needs a bunch of customized shaders, it will distract you for months, maybe even years, except you have a dedicated shader programmer in the team. But suggesting that a lone wolf should do all this on his own is probably not a way to succeed.