Posting Note: I used Google to find the above information at the above link. It was there. I coped the above from there. When I attempted to re-use the link, it's been taken down.
I just went to the link, and the paragraph you quoted ("For mental performance. ...") is still up.
I noticed later that it was back up.
I tried four or five times to call that up with the page link and with the Google link.
Neither would call it up.
There was a note about it being down for repairs of some sort.