The Dragons are one other view on the problem of the software complexity. If you want overcome Dragons, you must concentrate not on the measurements. You must find ways to reduce the complexity and prevent the addition of new problems.
Most problems of software development are psychological problems. Only few experienced professionals are able observe and describe them. Most people feel that something is wrong, but cannot understand what. Dragons are a good psychological method to activate hidden knowledge. One can describe with metaphors the things he cannot formulate any other way. Dragons are partially a fantasy, partially a game. Even the others cannot understand the proper interpretation, they can feel it.
One other good thing is the personification of problems. Abstract dangers don't impress. The people know what ``should be done'', but don't do this. A Dragon is a good ground to make things right. Even a virtual Dragon is more real for a human than hundred tables, diagrams and guidelines.
For instance a developer doesn't write ``useless comments''. He knows the purposes of comments, but won't waste time for such things. He thinks that nobody will understand the source code wrong. If the developer knows about the Dragon of The Source Code, he knows the face of enemy and has one other position. He understands that he must explain what the code does, because the Dragon has evil nature. If he don't write about possible problems, the Dragon of The Source Code want to use them to introduce errors in the program. The programmer now protects the code from enemy. This is much more effective than to follow abstract guidelines.