By no mean is this impossible. I suck and yet have golded this. But there's one trick I learned from the ghosts of the top guys that helps, and that's that turn 1 takes an early turn-in, significantly earlier than one might think. You'll be carrying a lot of slip angle to the apex but the idea is to get the thing pivoted quickly so you can get back on the gas quickly.
Then you have to concentrate on not bleeding too much speed in the following chicanes -- do it right, and you can nearly straight-line the second set of turns.
The second big left on the back side of the course requires heavy braking before you turn in, heavier than does the first left. They look similar but aren't. I lost a lot of time there until I acknowledged the difference.
Another trick, good for getting gold but not moving up the leaderboard, is just to go a bit deeper into all the big turns before initiating the change of direction and then making sure the change happens very fast.