Well that is certainly one way of looking at it.
I always figured that those of a lesser mental capacity required more instruction to accomplish the same tasks that others just seem to pick up naturally or with less issues. I think the Stihl engineers and document writers have shown an incredible amount of patience by providing additional reading materials as learning aids for those that can't just simply figure out how to work a simple cap, like the rest of the population.
My kids can figure out how to operate the flippy cap. Here is an instructional video for those that can't figure it out. If its too fast for some of you then use the pause button or slow motion.
Sam