Wait a minute - in your previous message you wrote that you work in stereo only, but now you want to open three or five outputs ...? I can't follow your train of thoughts. 8-/
I didn't say I work only in stereo; I said I produce for stereo:
"I'm producing for stereo, not surround".
What comes out of my DAW is stereo. That is different from what comes into my DAW.
Imagine someone using a real mid/side microphone. The microphone outputs one mid-channel, and one side-channel. That enters the DAW as one mid-channel and one side-channel. But that is not what the final listeners hears, because it's not what eventually comes out of the DAW. In the DAW, you mix the mid/side channels with your faders, and then you transform the mid/side system into a Left/Right system, and then you render that Left/Right system to a WAV file, and when the person at the end listens to your music, he doesn't hear Mid coming out of one speaker and Side coming out of the other speaker. He hears Left/Right stereo, because you used your DAW correctly to process the information from the mid/side microphone.
This is but one of many examples how a DAW can output something different from what enters it.