ED is a system designed to benefit the colleges and their agendas.
It benefits them to lock in students who they are absolutely certain that they want.
It does not benefit them to lock in students who are not clearly offering something better than they will be able to get in the RD round, when they may have many more students to choose from.
Things the colleges want are:
-specific qualities that fill their goals, which are not otherwise easy to come by. Those are the “hooks” – recruited athletes, meeting diversity goals, etc.
- qualities that benefit their overall stats, for whatever is important to them.
- full pay students, as many as possible
So higher than typical SAT scores can be a “hook” in some cases if the college wants to keep its numbers up.
Anything that does not benefit the college as compared with what will invariably be available to them in the RD round is simply not a good reason to support ED admission. That’s the mistake in thinking that an applicant with weaker-than-typical stats will get a leg up somehow because of the higher admit rate in the ED round. If, for example, the median SAT is 700, then there is no benefit at all for the college to admit the student with a 650 in the ED round - absent other value-added qualities (i.e., “hooks”) – in that case, it is merely tying up a spot with a student whose numbers are bringing their stats down, creating extra pressures to find higher stat students in the RD round.
No one can ever say what was in the mind of the ad coms, but in the RD round, the college also has to consider yield. Students are most likely to accept an offer from a school which either is the “best” (most selective/most prestigious) school that admits them, or the one that offers the best financial aid (or a combination of both). So in the RD round, the agenda might shift somewhat, depending on how well goals were met in the ED round.
For example, if a lot of very high stat students were admitted ED, then the college has more flexibility to offer RD spots to students with somewhat lower stats who may also be somewhat more likely to attend, while perhaps waitlisting higher stat students (who might be assumed to be likely to get into competitor schools that tend to win out when students are admitted to both).
That RD applicant obviously still needs to have something that the college wants, but the college agenda and goals would have shifted.