It irked me just a little during that 2012 fight scene that future-Cap didn't just utterly demolish past-Cap, skill-wise. He does beat him, yes, mostly due to surprising him about Bucky, but the Russos themselves have even made a point of acknowledging in interviews/commentary that between Avengers 1 and Winter Soldier, Captain acquires a bunch of actual fight training, whereas in his first 2 movies, he's mainly relying on his endurance/strength/natural reflexes to scrap through the fights. Then again, that wouldn't have been a very fun action scene if he took him out in 3 moves.