The benefit to an "OPEN" regular crawl:
It it will do a full sweep and unearth links you *didn't anticipate.
​*note: it will not unearth orphan links since our crawler can only pick up urls that are actually referenced by other pages.
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The benefit to a CSV Crawl:
It will ONLY crawl the URLs you listed, and not follow any links on the pages it finds.
This is useful to show a specific isolated group of pages for perhaps a user-specific flow/scenario.