Imo it is not possible for google to detect properly spun content, it is not worth computing power it requires. They can do this using ngrams for example, but it is uses a lot of queries. And for example article spinner I coded beats this algo, so google cant detect that the content is spun. Manual spinning is also good but it takes more than 30 minutes per article.
It looks like the creators of Spin Rewriter 9 .0 have really put a lot of work into creating a piece of software that creates readable content. However, Google isn’t stupid and there are a lot of things that can go wrong when you are trying to “manipulate” Google into giving you more traffic. Google hates spam, badly written content and duplicate content. These are all things that Spin Rewriter 9 .0 is capable of creating. You simply can’t trust a piece of software to write content for you in my opinion.
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