Bonk, I assume the coke effect is a sort of superhuman feeling and having your ship disintegrate around you from engine doubling?
Roughly, yes. That is an apt description.

It is referred to as the "cocaine rule" as for every turn warp doubling is on, one warp box is destroyed, so the more you use warp doubling, the more you need it; until the downward spiral results in a crippled husk of the ship you originally had. So use it sparingly and judiciously, ensuring you have enough spares to cover the damage to prevent a dependency situation.