TMBTM said:

I don't like that. I think it's important to show the conflict in him.

Well I understand, but I think there's enough scenes to show the conflict (the few lines that follow that scene for exemple). It is also important to show a darker side of Anakin. Once Obi-Wan is not there, he is not afraid to let his anger free. By the time of episode 3 we can assume that Palpatine already have a strong influence on him.

Exactly, that's what I was thinking. He's not afriad to let his anger out when Obi Wan isn't around to tell him otherwise