Please share the video you are referring to, as Joe Gilder has a large number of Studio One videos.
From what you are describing, I don't think we are talking about the same thing.
I am talking about a button you click when you have finished your production, which then takes you to a new mixing screen. And then another button you click when you are finished mixing which takes you to a mastering screen.
All the mixdowns, stems etc... are automatically handled when you click the button. And everything remains in the same project.
I have not seen that feature in StudioOne or any DAW in fact.
There is always the need to produce, then export stems, new mix project, then mix, then mixdown, new mastering project then master, then mixdowns.
Or you need a supercomputer and can try and do it all in the same song. Which I try to do, but it does not work well as you really do need a supercomputer.
What you have described, if I understand it correctly, is separate projects and some way of switching between them. Not as elegant as described above.
Please send the video link, so I can understand what you mean better.