Push up a full blade of dirt and then see how easy it is to turn by hand – hence the more powerful cylinders on the angle. Allows you to direct the load while in motion. Does that answer your question?
Maybe, guess I never used that function. My experience with blades were always on tractors until I got the dozer. Now I learned a new use for the 6 way blade, will try it out when playing around in the dirt.
What Tontosgold said is true. You also need more strength to hold the blade in position when sidecasting, especially when the blade is also tilted. You will find these cylinders to be larger on any dozer with a six-way blade.