I've received over a dozen copyright removal notices and have always replied: "for educational purposes only, original performance protected under fair use." I have not lost a dispute or not had a video reinstated yet. My videos are not monetized. I think putting footage of yourself playing via webcam helps your case as it does then qualify as your own performance, just a noteway with the mp3 would definitely be a grey area as far as infringement I would think. Just a sidenote: the whole infringement/copyright strike thing is ridiculous, you can find ripped MP3 audio tracks with millions of hits all over Youtube that don't get touched... yet Rocksmith educational videos that have hits in the hundreds seem to get targeted.