IMO, JB isn't going to let her take a plea. I think this could've been over long ago if it weren't for him. Remember that time in the car with LE - when they said they could either go somewhere and she would give them info or she could go to jail? She chose to talk but said she should ask JB first. He, of course, put the nix on that and told LE to just take her to jail. He's not going to let her take a plea. This high profile trial is his time to shine (or so he thinks). This is exactly why the bar investigated him for having a hidden agenda. IMO, he definitely does.
Not being disgreeable, I promise-'cause I think JB is a stinky atty...but I believe KC just wanted to dodge the cops that day, but did not have the fortitude to do it-I think she hid behind JB...When he arrived at the station, he seemed prepared for them to talk-but then he asks KC if she wants to talk to him first (her face looked tentative), and she said yes almost before he was done with his sentence.
Now, you may be right in that when he spoke to her privately, he pointed out what she could get herself into if she did this. As her legal advocate, it is good for him to let her know the legal consequences, but a fine line between that and telling her that she should not talk to them. At some point, it becomes selfish, like he just wants to win, or wants to be his client's hero. Even though he is her legal advocate, there to make sure the law is fairly applied to her, it is not okay, IMO, for defense attorneys to block justice for the victim-Caylee in this case.
If JB told her not to say something that she really wanted to say, he would be blocking justice for not only Caylee, but for KC.
ETA-Tying back to the plea topic, if it is the best thing for KC to do at this juncture, her attorneys need to let her know that, and not allow KC to lead them around by the nose. She has to be sat down and told about the real world at some point.