Perhaps I am overestimating the extent to which the outcome is engineered; maybe the formula simply produces that outcome.
Examine 2002 when these same three schools and Penn were in an unwieldy four-way tie. I consider it PC that USNews, in order to avoid upsetting the school that happened to be a modicum shy of the others by placing it last amongst them, deems their proximity a defacto tie. Especially when you are discussing this tier of schools, finding grounds for differentiation should be a necessity.
My argument, as I say, rests upon the premise that you are going to employ rankings as a tool at all. If it's there for us to use, make it as precise as possible. If Boalt is 10th and Michigan is 8th, say so.