<p>Well, if OP’s GC routinely writes a 2 page letter and is in touch with colleges, this suggests a more elite high school. Yes, an adcom who’s used to hearing from the GC will note if a particular candidate from there does not get the same treatment. Among the unwanted assumptions could be: either the kid isn’t on the ball and missed informing the GC or the GC is not endorsing this one. So, for OP, best is what he/she is doing: talk to the GC.</p>