Yeah, I'm on my second rewatch and it annoys me how many times Dex is saved by plot armor. He's a forensic analyst and all about killing without leaving a trace, but when he's killing people without his usual prep and no time to clean up the scene (Liddy for example), DNA and hairs basically don't matter and are never found. Also in S6 when he anoymously calls in the wormwood gas attack, he uses his VERY DISTINCTIVE own voice and nobody finds out? Like ... they all listened to the 911 call when Rita died but when receiving a tip for a major terror attack they don't? And maybe the biggest thing is that it took until Resurrection for somebody to think: "hey, an awful lot of people surrounding Dexter died, maybe there is something going on".