When I say the mystery plot seemed well thought out, I don't mean in a complex way, just in a completed way. For example, I'm working on a fic now. I can't seem to finish it, because I've shoe-horned the case in so poorly, that it feels like everything comes to a stop with Harry and Perry talk about it. I'm trying to fix it. Your fic, though, doesn't feel like that. When they discuss the case, I totally get how they feel about everything going on. (BTW, when and if I ever post my fic, I didn't steal the thing about Harry hating stakeouts from you. It just happened that way.)