[verisimilidude]

It's not going to work with the Ivies, in the US, because the whole process will surely become scattered. Each remotely capable school will find a way to game the system and get qualified. You're really screwed if you go to a school that cannot qualify, which would likely include most of the students who need this help the most. The system is still money chasing money.

The only way this works is through public education, where the K-12 system is tightly coupled with an elite public university system, and public policy can drive both into a tight partnership. There's a system somewhat like this in California called TAG; any student who signs up and makes grades in community college can usually get guaranteed entry into a UC. It only works because the California community colleges are required to teach all "transfer courses" at the UC level in terms of content, etc. It might be possible to extend this kind of guaranteed enrollment down to K-12.