For a while, I noticed that YouTube keeps buffering HD videos at maximum speed for the entire duration of it until it's fully buffered, but not the same happening when you select the 360p quality. When you select the 360p quality, it buffers for a bit at good speed and then slows down to a crawl. Sometimes even pausing the video in a middle, because it didn't buffer enough.
Here's a quick video I made to somehow show what I'm talking about: http://www.multiupload.nl/F08M0SWDP8
Now it doesn't bother when you want to watch the video in fully from start to finish, but it's a bit annoying when you want to skip some parts in a video and it needs to rebuffer every time.
Any reason YouTube does it, and only does it at 360p quality?