It amazes me that people still don't understand the way in which these season arcs are set up.
One thing that is going to lead to a shitload of tension throughout the rest of this season is simply how many times Dexter has ****ed up already.
Killing the guy with a grappling hook and no gloves, killing Boyd without much cover and shoddily constructed kill room, now having a living witness.
He's effing up bad and the noose is going to start to close.
It's a slow burn, and there's nothing wrong with that.