Learning music from recordings (video or just audio) would be so much easy if modern video and audio playback software would bring back the AB repeat function that used to be common on CD players, DVD players, LaserDisc players, and MP3 players.
Check out Soundslice for exactly this. It's great audio/video playback (with slowdown, looping, etc.), with an integrated tab and sheet music editor. So you can write down what you've figured out, and it remains synced with the original audio.
Why the heck did this largely go away?