“First Blood” was a mixed bag of a midseason premiere, containing a lot of cool things – but also a few wonky elements.
Firstly, it doesn’t exactly track that Dean, and assumedly Sam too, would think six weeks of solitary lock up in an off-the-books black site would be worse than Hell. In fact, this actually felt like a punishment the two of them could do in their sleep. Meaning, you could probably check back in on Dean a year later, open up that cell door, and he’s smirk with a full beard and say “Is that all you got?”
Also, they were never even in the dark and having the lights turned off was a specific threat.