User blog comment:SayuriDarling/The Blood of Olympus Official Discussion/@comment-25514010-20141011093057/@comment-25285541-20141011104632

Think about it. They were the best in HoH. It wasn't equal as those 4 were the leads. RR had to even it out a bit. And on top of that, Percy and Annabeth  dominated the PJO series. They've had there time to shine for 6-8 books. So even if RR did put their POVs in, they wouldn't be as interesting as the others.