No. For starters, escape from the SS does not depend on gravity assist. So we're not trapped. Nice try. Please Register or Log in to view the hidden image! What I am saying is: 1] The sun cannot be used as a gravity assist. Any speed we might gain falling toward it is exactly lost when we rise away from it. So it does not do anything for us with respect to escaping the solar system. 2] We can use the planets to change our velocity with respect to the SS. Which is what all our satellites do. 3] But gravity assist is not applicable in the two body scenario you posited many posts ago.