[sespindola]

They're probably using DASH[1]. The video is split into several segments and therefore the player will fill the bufer only until the end of the current segment.

Below each codeschool video you have a download link, so you can view them offline.

[1]: http://en.wikipedia.org/wiki/Dynamic_Adaptive_Streaming_over...

[aaronm14]

I see that's probably what it is, thanks for the info. I will probably just need to download them.