It happens, but I've also experienced the stream playing flawlessly for the first 30s and then severe buffering for the remainder of the video, or the ad buffering and the video not. Network conditions change and buffering happens, but i haven't seen a consistent trend where the content is worse than the ad, like i have on so many other video players.

I am on a network with absolutely terrible latency. 500ms at its best and almost 7 sec at its worst. You tube videos will actually load and buffer... his "unskippable ad", will not.

Sometimes I have to wait 5 minutes to get through a 30 second commercial.