Okay, here's my list of "they should have known better"s.
Roger should have known better than to wake everyone up making all that racket after they've had a late night. Being the only one on a different schedule is just plain stupid.
Christy should have known to always use "rock" in "rock, paper, sissors"
Butch and Dave should have known to not blindly assume they are back in their old alliance. I don't know if it happened or not, but they didn't show them making any effort to even check it out -they just assumed.
Heidi should have known better than to take her clothes off and talk about threesomes on national tv if she's planning on going back to her teaching job.
Heidi and Jenna should both realize their bodies are not so sexy at this point.
I think the jungle is starting to get to them all!