You know what I find truly remarkable about this scene? Is not just that she JUMPS OFF A SPEEDING ALIEN VEHICLE HUNDREDS OF FEET ABOVE THE GROUND but that she knows the EXACT MOMENT to make the jump to not only hit the roof (which, at that height and speed is an incredibly small target) but to hit it at a point where she isn’t going to a) immediately crash into a wall or b) be carried by her momentum over the other side and down a gazillion stories to the ground.
Natasha had to calculate IN HER HEAD IN THE MIDDLE OF A BATTLE the velocity of the alien vehicle, the size of Stark Tower’s roof, how high she was above it (so she wasn’t so high she’d be killed just by the fall to the roof), how long it would take her to make the jump successfully, what position to hit the roof in to minimize the physical damage, possibly even half a dozen other things. A miscalculation either way—too soon or too late—would’ve killed her.
Yeah, when she describes someone genius-level smart in CA:TWS as “slightly smarter than her but only slightly,” she’s NOT KIDDING. Natasha is probably either just as or very nearly as smart as Bruce or Tony or Jane or Betty, her training just meant those smarts were put to use in a different way. And that it’s something she’s trained to manipulate people’s expectations of, just like with her sex. IMO, if Natasha asks to have something explained, it’s not because she doesn’t understand, it’s because she doesn’t want the person she’s asking to KNOW she understands. Because her stock in trade is getting people to underestimate her and then using that against them. And this scene is the proof. Because when no one is watching, she is BRILLIANT.