Since Airbus thrust levers do not move in auto mode there's no spring, any mechanism or cables that can cause any undue friction. They slide evenly when pushed and stay where left. And since it is FBW their position just signals the required thrust and their rate of movement selects an acceleration schedule. If you slam them it selects the fastest schedule. The problem is if coming from other aircraft you are used to large movements. It can happen even with the stick but since the arm is rested only the wrist comes in play. That's Why Airbus insists on proper adjustment of the active arm rest. Compared to yoke movements the stick moves an inch or so. Again takes getting used to.