Just to add to the discussion, some weeks ago or so, I blasted one of the worst SEOd YT videos I have ever seen, with the worst content and the worst kind of spun content in the backlinks and in 2-3 days it ranked for its kw in #6.
Funny thing that this has been the worst/loosest test site I have ever done without caring about anything. Also its searched around 30 times a month or so, yep really low searches.
Anyway, here are some pics:
(I only leave the URLs as they are kinda big)
1) This is the rankings graph:
http://i.imgur.com/LuVuIRh.png
It took about 2-3 days to rank with mass spam.
2) This was the only "article" I made in the campaign:
http://i.imgur.com/1i2fLOi.png
If you look closely, you can see that I copy/pasted the default comments spintax in the article 2 times

(Hehe talk about unique content). For the title I also pasted the same default comment spintax there lol
3) These are the engines I seleceted and posted to:
http://i.imgur.com/cIJyx4X.png
Yea, almost every link I could get my hands on.
The video was uploaded in June 18th, no views/comments/likes/subscribers/followers/shares/pins were added to the video. It was uploaded and waited a few days and then the spam started.
Looking forward to test this in more kws with a little more searches to see what happens.
With this being said, there are no true "waiting periods" or stuff like that. Maybe Matt is just playing darts in the serps and sandboxing the lucky ones
Seriously, let's see what happens in the coming weeks/months.