This is a very good article about the academic index and Ivy admissions: http://www.nytimes.com/2011/12/25/sp...ath.html?_r=2&
If she gets one of the track coach's admission slots (and there aren't many of those), she will have a much, much easier time getting admitted.
Bear in mind that all college coaches contact countless kids, court many, and actually offer few an admissions slot. They dump many, so she can't think that she has one of the slots until she gets a likely letter.
Just for this reason, she should keep many schools in the game. If her times in high school are comparable to those at the Ivy championships, many, many schools will be interested in her.
By the way, I read somewhere (can't find the source right now) that Princeton's average academic index for athletes is 214, and the school's average overall if 228. I would guess that Yale's numbers are in the same range.