If I just leave my hubs alone, then not many people view them. However, if I amend small details, such as hub title, I get a lots more traffic. Does it post it on a news feed when you change/amend a hub or something?
I think it is to do with the fact that Google loves updated content. If you keep your hubs updated it can help to boost the Hub's SERPs. Your Hub may climb closer to page one of Google when you make small amendments because Google sees that your page is fresh.
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