It's a difference between knowing how to do it, and doing it with style. The markup implies quality in the first place, because others are supposed to work with that code. And if the markup is bad, then all the website is going to be shit (and I mean viewing it will be a pain in the ass, SEO will be very bad, this kind of stuff). It's like anyone can write code. Some can write code that doesn't work at all, some can write bad code that works, but only a few write quality code that works.

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