Your process seems to privilege your current model over new models with identical predictions, which leads to belief hysteresis. Your point has also been fully answered in his sequence, so either you didn't read it, forgot, or you're deliberately strawmanning. And I wouldn't sau that decoherence doesn't have interpretational baggage, did you read the article you linked? Because it says under the interpretation section that copenhagen didn't use decoherence and it's at the core of mwi. And you're lamenting Eliezer's loss of rationality based on what, again?
Today's post, Decoherence is Falsifiable and Testable was originally published on 07 May 2008. A summary (taken from the LW wiki):
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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Decoherence is Simple, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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