Why did Spagnuolo stink as Saints' DC? (merged)

Long article on The Athletic today about how Spagnuolo improved the Chiefs defense and how he's been a great DC everywhere he went. Of course, it fails to mention Spags' terrible stint as Saints' DC. Why did Spagnuolo fail in New Orleans?

Here's a comment from a reader on The Athletic (maybe a SR.com member?)


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Mike Detillier said it wasn't a fit. For what it's worth.