Answer:

Fibonacci relationships have important application when applied to most, standard (orthodox) Elliott Wave patterns. But, around 1990, when Mastering Elliott Wave was released, new forms of price behavior began to emerge. That new price behavior, I suspect, was the market's way of counteracting growing interest in pattern recognition and the popularity of orthodox Elliott Wave concepts.

It was around this time, out of necessity, that NEoWave concepts and formations were born. NEoWave added logical concepts (to the orthodox theory) to deal with the increasing complexity of wave formations that were developing, such as NEoWave Diametrics, Symmetricals, Neutral Triangles and Reverse Alternation. These were new types of market behavior that orthodox Elliott Wave could not explain or interpret.

In the late 80's and early 90's, the study of Fibonacci relationships also reached a zenith. Again, the market made adjustments to counteract its popularity; as a result, the new NEoWave patterns mentioned above began to develop without the presence of Fibonacci relationships. As a matter of fact, one of the crucial features of NEoWave Diametircs and Symmetricals is the absence of Fibonacci relationships.

Since 2000, I have seen dozens of NEoWave Diametrics, Neutral Triangles and (to a lessor extent) Symmetricals on both smaller and larger time frames - many of them lasting months. Because all three of the above formations have proliferated for the last 10 years, and because they develop without the presence of Fibonacci relationships, the value of Fibonacci (since the stock market top in 2000) in the study and confirmation of wave patterns has declined significantly. That is the reason you rarely read about it in my current and past NEoWave updates dating back to 2000's high.