Jamie,
I guess I am wondering if there is something specific that you wish to accomplish with the skip. Is first grade notoriously boring for kids at the school? are there no teachers who are good matches for GT kids? Will the school be unwilling to do adequate subject accelerations through elementary? Are your daughters unhappy, bored, getting lazy intellectually?
I have a son who is perfectly capable of skipping and has even casually been offered one by the principal. But he loves his class and is getting most of his needs met with subject accelerations, so he has no real need or desire to skip. Each year he has been in school has been useful to him in many ways--with each teacher having something unique to offer him. We would have bee sad to miss any of his elementary years. I know we have been lucky in a variety of ways and that under other circumstances we probably would have seriously considered a skip. Each year I worry that this will be the year that there will be problems, but he's in middle school now and everything is going great.
I just think a lot depends on the child's personality, their attachment to their classmates (especially for girls social relationships can be important), and the schools ability and interest in meeting the child's needs creatively. These factors are just as important as the test scores.
