I fly AA, and generally get upgraded, the few times I don't I'm in an exit aisle seat. The FA (shortly before take-off) comes by and gives the usual info re exit aisle seats. I am at that moment comfortable with the responsibilities of being in an exit aisle seat--but in the event of a real emergency, would I (not freeze and) open the exit door per instructions? I don't know, and hope I never find out.