Today, 4:31 PM · 54 replies and 1526 views.
First, OP You're either wrong or your game is bugged. Using planets as brakes works just fine. You just need to understand that not all planets are massive enough to brake all speeds. Controlling your orbital radius, speed, and dynamic throttle setting for maximum time-efficiency is a bit of an art form in Elite.
2nd, the rest of the post in this thread are wrong about physics. RL Gravity assists are used to increase/decrease velocity with respect to a 3rd body and the direction of the orbit. The game uses different physics for interplanetary travel whereby SC (alcubierre-type) bubbles are disrupted by the space-time curvature of gravity wells. This sci-fi game mechanic makes logical sense since we're talking about a highly localized curvature being disrupted by a larger scale radial-distance based curvature.