*Edit: I checked some of the stuff more out in detail. While some concepts on this are valid and backed up by sience, others like RSD are not. Use this as a springboard for learning, not as a valid source in itself. Yes it says so in the corner already. But spelling it out might help.
People are more complicated then a diagram from the internet. Never forget that.
If you made friends, it taught you social skills.
The problem with gifted students is that they can struggle connecting with those who don't enjoy abstract thinking, theory, etc, but at the same time it was one period of your school day, you had all the others including recess and lunch to learn that.
Not talking about social skills, and when I went to school, gifted classes were full time, from grades 4-8.
That seems like a really bad idea unless you had a very large school or that was just what they called honors classes. My class was pretty average at 200 students and there were only 5 kids in the gifted program.