The original post is mostly a cut & paste from someone who says,...

The original post is mostly a cut & paste from someone who says, amongst other things,
"I hunted it down online. A week later, the little white pills arrived in the post. Within a few hours of a 200mg dose, I found myself gliding into a state of long, deep concentration, able to read a book for six or seven hours at a time without looking up. My mood wasn't any different; I wasn't high. It was like I had opened a window in my brain and all the stuffy air had seeped out, to be replaced by a calm breeze. On Provigil, I had the most productive month of my life, writing reams of articles. I didn't notice any side-effects – until the third week"

Reference:http://www.independent.co.uk/opinion/commentators/johann-hari/johann-hari-they-were-great-at-first-ndash-but-then-the-creativity-dries-up-1708987.html

Is there less credibility for a report by such a person?

The original post is off subject and should perhaps be in the political forum, not here.