Bernerd the 'doer' wants to make a large sign so that they can be rescued, he is annoyed that Rose thinks he is giving people false hope. Whatever happened to the fire they had going at the beach? Don't you think someone would have noticed that?
The Henry Gale imposter torments Locke by not saying if he did or did not push the button. With his strong will it is hard for Locke to decide whether he should risk it and not press the button, which he has been pressing for nearly the whole season. In the end he carries on pushing it.
Jack and Kate go looking for the others and instead Jack gets a sore throat, then they find Michael.
In all this was a rather plain episode with no extraordinary revelations apart from the discovery of Michael at the end.