Airedale, while it is true that some aspects of Fed action are “fundamental events,” there are others that are not, and it is those other aspects that are extending the wave periods.
Hurst defined three different types of fundamental events at 5:17-18 in the Cycle Course.
Type 1 is sudden change with lasting impact, such as a trading halt due to fraud or criminal activity in a company which drastically alters prices for long periods when trading resumes.
Type 2 is an unexpected development, often favorable, that has less of an impact than Type 1. Price cycles may have greater amplitudes for 5 to 20 days, then revert back to normal. Type 2 events might include new legislation that benefits specific industries.
Type 3 is usually a favorable event accompanied by increasing volume and interest with longer term effects, such that a pseudo-trend is created. As volume interest subsides, wave amplitudes decrease and a steep pseudo-trend usually develops in a downward direction. Type 3 events have included removal of the fixed price for gold, world monetary crises, and currency devaluations.
The recent Fed action has had characteristics of a Type 2 event, namely, the short term spurt in stock prices caused by the unexpected rate cuts and lending activities. There are also the long-term effects caused by the devaluation of the dollar that can be considered a Type 3 event.
You are right that fundamental events, as Hurst defines them, do no alter wave periods. And the Fed's Type 2 and Type 3 fundamental events described above would affect amplitudes but not periods.
I’ll address the other aspects of Fed action that do not constitute a fundamental events, and that extend wave periods in a follow up post.
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