So if only 10 students are on this committee[1], that makes more sense. Either this has changed since the time of the author's story, or he misremembered, or exaggerated (re: saying that all 25 students, the whole student body at the time, was at his interview plus talking about his essays for days leading up to his interview). I understand that the idea isn't meant to scale up to larger schools, but it sounded like it wouldn't even scale to the number of applications that Deep Springs would get in any given year.
[1] Is this still 1/3 to 1/2 of the student body?