I wanted to just give an anecdotal example of what it might feel like to be Social.
One of my major social 4 quirks has been that I don't dance in front of people. I do love to dance as much as anyone does. In fact I really love it as a musician. It's a natural response to loving music. But the extreme shame of wondering what I'd look like to others or the separation I feel when others are enjoying some kind of positive group solidarity to music that I think is crap also prevents me from letting loose in public.
Last night I was listening to one of my favourite old disco songs and I ended up dancing my heart out (after closing all my curtains) alone. Even though no one was watching, I felt that everyone was watching. I was crippled from even being able to enjoy my natural response to music because of the onslaught of questions I had to answer for in order to even do this alone: Is disco cool? Who's watching me dance like this? Where are we? What genre would I be if I like this song? Should I tell people I like this song? Maybe I'll post about how I like this song and change my look to be disco-flavoured. Now I need to readjust my entire sense of how other people see me to fit the fact that I like this song and dance this way. Okay I can make this work, I just need to integrate it into my image. Is disco gay? Are people going to see me as a stereotype if I like this? How can I make it seem like it's uniquely me? Which group of people should I present this too?
Then the realization that actually I'm alone and no one is watching at all sets in. SO/SX wants to be some exotic bird; and combined with withdrawn 4 it's like being a beautiful bird that just sits in the corner and is admired but disinterested hoping that its feathers are enough to make people approach it.
Throughout all of this, I had a precise picture in my head of exactly which people were watching me dance and where and how they were reacting. And with social adaptability, I had to readjust my entire sense of what my role was in the eyes of others before I could even just simply follow my gut enjoyment (being SP blind and gut last plays a role in this too).
I'm sure many people can relate to this brand of self-consciousness. However having high Social in your stacking can bring this consistent "mentalizing" or processing/adapting to your role as others perceive it. It took me years to be conscious of these thoughts.