Rocket League – Is It Possible to Use Multiple Boost Trails?

The game uses quite a realistic physics engine. The ball is modelled as a sphere (roughly) and each car has a cuboid hitbox of slightly different dimensions. Therefore things like the tilt in a dodge or an aerial (using air roll) alters the trajectory of the ball after impact. Spin does affect the ball when travelling through the air as it curves towards the direction of spin but not when travelling along the ground (at least not noticeably). Obviously the angle at which you hit the ball is going to have the most effect on its trajectory. Collisions in the game are purely Newtonian and momentum based so boosting and driving at the same speed will have the same effect on the ball.

On a gameplay level, its best just to go in to free play and get use to the mechanics of the game instinctively so that you can judge what your touches will do to the ball.

Yes, it does work. Just tested it myself. However, your window to demolish opponents seems a bit smaller. I had to hit them in mid-flip just after going supersonic. Otherwise I slowed down too much after the flip was finished.