I am guilty with this, but I can say that only at certain times

I usually don't get angry when talking to persons having difficulty in understanding what I am saying.

I'm pertaining to those persons who don't REALLY understand me or those persons who was clueless to the things that I am saying.

I usually help them understand me clearly, but there were certain people who Acts ignorant.

I know someone who really was smart, he really is knowledgeable in many things especially to educational stuffs but he has this really annoying habit.

He always acts that he didn't know what we are talking about, he always acts that he was clueless to the topic we are discussing.

I always get angry when he was acting like this and a fight will surely began

He always say that he do it because

"Acting like an ignorant people was his delaying tactic to have more time to think"

I really don't get why he is acting like this, even in crucial time where we are rushing in doing our projects he always act ignorant and really make me angry

I guess I do get provoked to those people who ACT as an ignorant person, but talking with really ignorant people was OK for me