Seems more to be how to download and burn Windows 7, not really any installing going on. Also this may not be allowed due to the frequent torrent programs and specific torrent sites mentioned. I know they're not illegal in themselves but I wouldn't be surprised if the post dissapeared.
Yes, the video dude mentions the pirate bay like it was nothing.
Honestly though, I see nothing wrong with downloading the Windows 7 RC as a torrent... it's just irritating how lots of people seed those modified versions which are actually very risky if you think about it.
The how-to OP linked to (which is his btw) contains info on finding those valid Windows 7 RC torrents.
There's no need to risk downloading it from a torrent anyway. Microsoft's partnered website, where I downloaded it from, gave me my maximum download speed.