The fact of the matter is that if the Nexus 4 sold out in less than an hour, then they must not have even had stock to sell to the people that signed up for "notification".
Another thing to consider (and this was true of the Nexus 4 and later updated in the article) the article said they 'sold out' but Google didn't. The authors interpreted not being able to get to a sales page as being 'sold out' but later discovered that there was some order rate management going on where the 'overflow' went to the 'coming soon' page and repeated attempts would eventually get you a page you could order from.
Logistics management is a tricky thing, if you are good at it you can pretty much name your own salary because its trivially easy to 'show' how much you are worth with basic accounting techniques. If the company has the volume you can literally say "If you hire me I'll save you $700,000 a year, I'll actually save you $1,000,000 a year but I'm going to keep $300,000 of it as salary."