That is certainly one of them. In some circles, yield protection is also known as “Tufts Syndrome,” which is a bit of a tipoff. Some people also think Chicago fits into this category, and various other universities and SLACs.
This is a complex issue because once you offer ED, that is also presumably pulling some of your most interested applicants out of the RD pool, which will likely drive down RD yields. But generally speaking, the logical candidates for this effect are colleges have that have one or more notable things going for them, at a level that will attract highly qualified applicants, but in circumstances where those highly qualified applicants will likely prefer other colleges with similar virtues if admitted.
So, colleges in a really popular market like DC or Boston, but are not considered at the top of those markets as per things like widely-publicized rankings, but not too far down either, are one general class of possible candidates. That covers colleges like American and Tufts.
Chicago is an interesting case because way back before ED, it had a notorious yield issue, and indeed it ranked pretty poorly for such a well-regarded institution in things like revealed preference studies:
Chicago was only 27th in that study, and then in its own region, it was even lower at 29th!
So even though no one is necessarily “overqualified” for Chicago, it is still plausibly a place that could have a yield model indicating a lot of very well-qualified RD applicants are very unlikely to yield. Which becomes a signaling problem if you would really prefer Chicago over, say, Penn (12th on that list).
No kidding. My S24 was considering WUSTL for an ED2, and so I looked into it and they swear they will consider ED admits for merit scholarships equally along with RD applicants. But I encountered a lot of people skeptical about that. Of course it would make sense for WUSTL to commit to that if it helped promote ED applications, but some people just don’t believe such things.