At home I used Centurylink's "home" class of their DSL connection. At work we had Centurylink's dedicated ethernet connection. I could never really watch youtube at home because it would pause, buffer, play 5 seconds, buffer, etc. Once I VPN'd into work (which was 2 miles away) I could watch youtube without issues.

I'm sure it's a technical issue or something, but that is my experience with Centurylink and Youtube.

Now I use Verizon and only have issues with youtube when it's "congested."