I've just infiltrated the Harvester's Hideout and I'm trying to Ghost my way through. This means lots of non lethal takedowns. Standing enemies are pretty easy to lure wherever I need them to be (so that they're out of visual range of their buddies before I beat their face in) but sitting enemies are a problem.
Even though I'm right behind him, the game does not allow me to perform a takedown while he's still sitting. If I move in front of him, he sees me. If I want him to stand up, I have to get out my silenced 10mm and shoot something in front of him so that he gets up to investigate the noise.
Is there a way to reliably perform takedowns on sitting enemies such as the one shown here?