Past few years have seen a lot of changes from Google. Lots of changes in terms of quality and lots of changes regarding scraping out the spam. Panda and Penguin updates were the major ones. Have content strategies for SEO changed too? Of course they have.
Not only content, generally all Search Engine Optimization changes from time to time. Although a popular notion amongst all SEO experts is to get the web page to be the best user experience and yet make it readable to search engine bots. That would be a perfect implementation of any strategy.
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