Basically, if you KNOW your child from the inside out, and you have a great deal of ability to advocate strongly and effectively, and you have a cooperative school system, then yes it can work.
Yes, this. I think a lot depends on the personality of your child and how well you know your child. For example, my kid is the type who does not like to stand out much. Since he's a blender, the teachers did not see that he was in need of anything different. We got some complaints of boredom at home, and we could see by the work coming home that our DS knew this stuff years earlier. This required a lot of advocacy to get the school to do anything, when the kid appeared just fine.
My kid is also globally gifted, so a full grade skip (or two) was just fine. If you have a more lopsided GT kiddo, you will want a very flexible school that allows subject acceleration. If you have a very independent learner who is crazy advanced in or passionate about certain subjects, you may have difficulties finding teachers in elementary who can accommodate this subject. That may be a good subject to afterschool (finding mentors, etc.) So many factors, but definitely there are ways for EG/PG kids to succeed in public school. The elementary years will be the toughest, because there is so much repetition.
