LOTRfan85
Super Freak
I thought Cap said he didn't know who had killed the Starks, but knew they had been murdered by Hydra? Wasn't Tony under the impression his parents had been just killed in a car accident like it is meant to look? He mentions their car accident in his talk with the students at the beginning of the film after showing them a false memory of his past.
They do mention this in Winter Soldier when they are underground, HYDRA has been using assassins to take out some of the most important people. Steve has an idea of what is going on, but I do not think he had any idea who murdered Tony's parents, that completely blind sides Steve when its revealed on the video