Wingtip weight should be determined by how it flys, both inside and outside loops. However the article kind of mentions that the asymetrical tip weight is more for airplanes that avoid actual acrobatics.

The effects of the weight of a horizonally mounted engine is very small (yes, lots of weight, but a very small moment (distance from center line)). On pylon racing models, weight usually ends up on the right tip even with the engine side mounted with the cylinder on the right side as well. The reason is that in the turn, which is just half of a horizontal loop, the increase in the angle of attack makes the prop blade on the right side of the airplane do all the thrust, while the other side is doing very little if any.