Oh is that why my Coursera videos suddenly won't buffer for more than a few seconds? I figured it was an optimization, like with YouTube, so they don't waste bandwidth loading videos for people who have the tabs open but won't watch them.
I don't think there is one. You can't even compile a custom Chromium because it doesn't have h264 codecs. I even spend a day reading the Chrome source code, hoping there was some combination of headers that could trick Chrome into using the media cache, but I didn't find anything. I probably should have just spent the day finding a better CDN.
Do you know of any workarounds client-side?