>>42
id games do not have the production value of tech demos. They spend tens of millions of dollars on them. Clearly they don't consider them tech demos.
And Unreal beat out the Doom 3 engine largely because of better tools for artists and better support for outdoor environments. id lost track of this because they were too focused on making Doom 3, which was set almost entirely indoors in shadowy hallways. They eventually got around to fixing this with MegaTexture but it was too late by that point.