I think if they were going for yield protection they would WL someone instead of rejecting them. That way it doesnt hurt their acceptance rate but if the person actually wants to go, they'll probably show interest and get in and then Penn gets someone they would love to have.
i'll add my congrats as well. Penn seems to be strange...it deferred people from EA who looked like auto admits by their numbers. they deferred 7 people on LSN who had a 175/3.7 or higher. perhaps they are going for that mysterious "whole person".
i'm confused about this too. since my numbers are pretty high for penn (3.9, 175) i kind of expected to be rejected, because of this yield protection theory. so i'm wondering, should i take it as an insult that i got into penn with high numbers? they didn't send me a yield-protection rejection because they don't think i'll get into somewhere better? i don't think that is the case, but it kind of made me wonder