@
Rebelondeck, yes, any two types can co-exist under the right set of conditions. In particular, how much compromising they are willing to do, and how good they think a relationship can be.
Personally, I had no duals anywhere in my life growing up, and no examples of duals, so I thought that my parent's Mirror relationship (LSE-SLI) was a model of success. My parents seemed to get along, they rarely fought (but when they did, it was a blow-up, as if they had been harboring resentments for a long time), they loved and depended on each other, but they did nothing together, had no other friends, and their marriage seemed to be similar to two prisoners waiting out their life sentences in the same cell. My mother confided to my sister that sex was a distant memory for them.
I have pictures of them when they first met, and they seemed so happy. My SLI father had found an LSE woman exactly like his own LSE mother, only better, and my mother found a smart, hard working Delta introvert in law school whom she could boss around, who was similarly rational to and was a great improvement over her own old-country domineering LIE father.
Neither one was able to apply the kind of pressure on the other that they needed to be a working pair. Instead, they just kept to their separate ways and complained to us kids about the other one.
My LSE mother had a childhood IEE friend who lived in Denver with her husband, and when we were kids, our family went there to visit for a few days. I thought we had a great time, but we never went back. Recently, I was looking through old family albums, and I found a picture from that visit of my mother, my SLI father, and my mother's IEE friend sitting at a table. My father had the most unfamiliar expression on his face. He was happy, and so was the IEE, and my mother was looking puzzled and angry. My father still speaks warmly of the IEE. Ah, Socionics.
Having married (and divorced) a woman of the same type as my father, I can say that this method of selecting a mate (marrying a parent) leaves a lot to be desired.
With respect to the increasing divisiveness you see in Sahebette's and BuddyL's descriptions of their relationships, I can verify that that happens with Mirage relationships, too.
To paraphrase the inimitable @
niffer, Duality or GTFO.