Warp speeds above warp 5 were routinely used after 2370, without mention of the harmful effects, suggesting a solution was found, even though it was not mentioned on-screen. (Star Trek Encyclopedia 2nd ed., p. 187) See also: Variable geometry pylon. As the "speed limit" probably also limited potential future storylines, it seems that the concept was quietly done away with, shortly into the next season. Brannon Braga has noted that, "When you limit warp drive, the rug is being pulled out from under Star Trek." (Captains' Logs: The Unauthorized Complete Trek Voyages, p. 294)