For the dual sound processors offering two sound sources, I can imagine a streamer's setup, where you want to have your game sound over your headset and some music in the background via speakers. When I stream sometimes and I feel like turning on some music, it's kinda tough to get the right balance. Sometimes I only want the audience to hear the music but not myself. To achieve this scenario you'd need some hard to understand software or this motherboard. Simply set the voice recognition or your mic's sensitivity to a level where it can record the music coming from the speakers, while you can completely focus on the game's sound, because your headset covers your ears from the speaker's music.
Other than that... Maybe not having to swap any cables or disable the headset in Windows' audiomixer, if you want to watch a movie with le girlfriend?