A similar warning had come up when I uploaded Stonehenge, but with a fairly light restriction that still allows the movie to be played in America, Britain, and a lengthy list of other net-centric nations. Even so, I assumed the detection was made against metadata, as I had not only titled the post to match the song, but had even listed "Spinal Tap" as a keyword. However, in the second vid, I hadn't mentioned group, album or track (although it's possible QuickTime .mov files retain some of the MP3 metadata, which I was lapse in not purging).
Anyway, the long and short of it is that I'm heeding the recommendation of this post to simply switch to an alternate video host for potentially litigious clips. Annoying, and in my mind, counter-productive, because frankly some of these 60's- and 70's-era bands could use a little modern publicity!