Hi again,
I'm sorry that it took me so long to find the right words, but now you have understood the concept in its entirety. 😊
@Another User said:
If I am working in stereo only, is there anything to be gained by using the '3D to Stereo Downmix' and ' 3D Surround Downmix' presets?
While Ambisonics purists may raise an eyebrow, I think of these "downmix" settings much like the proverbial classical Tonmeister who uses all those beautiful surround and top layer microphones for the stereo mix as well. To my ears, they add a lot of spatial enveloping and tonal density to the reverb. - BTW, we have also done this with many mixer presets of our Synchron Instruments.
Apart from that, all these Downmixes rely on 3rd Order Ambsionics, not just 1st Order like the "classic" capsule based Output Formats, which is a huge sonic improvement in general.