I am in CA and my son had a "gifted" IEP in 4-6th. It was based solely on his OSTAT score taken in 3rd grade. I only remember seeing/signing the paper once at the beginning of 4th grade, and never hearing about it again. My son was enrolled in a special gifted class, and that is the only accommodation it had written on it. My older daughters had a IEP (K-11th) for LD's so I know how they are used & what they normally look like.
I can see how they can be used. It's a time to put in writing how the school will accommodate a particular child.
Not sure why others are concerned about IEP's wresting control from parents. An IEP is an Individual Educational Program, usually a student is tested and then there is a meeting with parents, counselors, teachers, principal that iron out what special accommodations a child needs. Ideally it gives a parent more control about what is going on in the classroom.