It reminds me too much of the spam mails that have a similar generated text to confuse spam filters. And no, I think you're wrong, it doesn't just replaces words by synonyms, I think it actually generates all-new text by using a syntax processor. If you read those articles closely, you'll see they don't really make sense semantically.
Imagine a tool that lets you enter the source code from a custom-designed web template that the designer had spent dozens of hours on and the client had paid good money for to have an original, quality design. This tool randomly changes ("rewrites") some of the code to make it look like unique work. Why should you have to pay for all that work when you can take someone else's work and get a variation of it at a fraction of the cost? Come to think of it, why should you have to pay for a car when you can simply steal one, paint it, and alter the registration number?
It looks like the same idea here except that it does this to web content: "You can have Article Bot re-write content into 1000s more pages of unique and spiderable content."
Imagine if someone did the above to work you'd created or paid for. Also imagine being the reader of content that the site owner had had manipulated from someone else's work with more interest in feeding the bots than in tailoring and polishing the content for site visitors.
Yes, I saw the part where it claims to create original content from scratch in addition to altering existing work. I have no ethical objections to that part of their services although I question the quality of the work. Hmmm...FrontPage designs just came to mind. Your choice.
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