As I recall, the scene where Banner is holding the spear came after the Black Widow "interrogated" Loki and realized that his plan was to unleash the Hulk. The scene doesn't play right because none of the others act upon their newly acquired knowledge in any rational way, such as landing the stupid helicarrier. The others actually get more abrasive! However if the implication is supposed to be that Banner has the Hulk under control, the scene with the Black Widow bringing him in plays in retrospect as if he's toying with her. And the attempted suicide story is either hysterical self-pity or a blatant lie. Well, the movie's about spectacle. And the Thor scenes with Loki remind us of the decent half of the Thor movie. And the Iron Man scenes with Pepper reminds us of the Iron Man movie.