Then why didn't he do that? It would have been easy to do. Why would he purposefully abstract his problem?
And seriously, everyone bitched and moaned about all spaces switching together. They all wanted to do it on an individual screen basis. Now they're apparently getting that and it's wrong all of a sudden? Wow.
Don't know the exact reason he didn't, but it could be 1. Assuming intelligence on the part of the viewer and 2. As people have noted, not wanting to show sensitive work to an audience nor set up a specific demo since it was just a quick illustration not designed to go out to an international tech audience.
Not everyone bitched about it. Many did. I didn't. Many others didn't There is no uniformity in macrumors land. I don't like full screen apps killing my secondary monitors. So i didn't use them. I would prefer a grid of spaces (more efficient to move between them) over a row, so complained about that with Lion. But it is a deal killer for me to ONLY be able to have a space per monitor setup. Luckily that doesn't look like it is the case with Mavericks. So this is an improvement, as long as Apple retains the option (which they have not always been known to do).
Noting possible problems with a setup isn't the same as saying either way is wrong. Just points out issues people using certain use scenarios should consider. For that, the maker of the video gets his accent mocked, his set-up derided, and his use scenario ridiculed. Welcome to Macrumors.