Oh, I know that developing country links are slow - I just thought it was a stretch to suggest that they are connecting to youtube so frequently after the page went from 2MB to 100 kilobytes that they shifted the average latency up.

It's okay though, sometimes a bit of hyperbole does a better job of getting the story across.

I think they were talking about just a small opt-in % of Youtube traffic, and that that percentage had a higher average latency than the rest of Youtube (vs shifting Youtube's entire traffic average).

The article states that the lighter page was opt-in. Thus a bias towards people for whom the heavy page was unusable is not surprising.