Continuing tagboard discussion with Jeremy:
So, the Time Travel in Avengers was KIND of like ours, in that it did create different timestreams. It was, however, also different from ours in that the changes they made to the past did not affect their own present, but instead created new timelines. It was a little more multi-versey in that aspect. It was a rather unique approach to time travel that I don't think I've seen in a movie before. I liked it.
But huh, yeah... the Necromancer DOES go back in time to get artifacts that he can't get in the present. I hadn't noticed that until you brought it up. He just had to do some extra scrubbing to put things back the way he found it.
Which, I guess, is what Captain America ended up doing. Wow, and Steve even came back to the present the slow way. Just like the Necromancer...
Wow. Maybe it IS the same. We didn't bring up the word "quantum" as much, though.
(I DO think Steve managed to stay in his own timeline at the end, though, because he had the Time Stone, and it seems to time travel in a different manner than the Quantum Tunnel. Alternatively, it is because people time travelling in their universe don't leave their own reality. Thus, he HAD to return to his own future, one way or the other. Staying in the past would be the only way he could actually change the past, because, by being there, he effectively created a new present.)