Matt Allington pulls out the dynamite:
OK, so what’s the problem? The problem is that sometimes you get such a deep, nested path of measures that the underlying formula is more complex than it needs to be, and it is virtually impossible to debug. If you simply explode/expand a final measure into the full, underlying DAX code, it makes it much easier to see what is going on. Returning to the DAX example above, this is what the third measure actually looks like under the hood, removing all references to the dependent measures
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