"skill"? That's bullshit, you can't tell anything about skill from a person's poorly phrased question. Especially since that person's primary language might not be English.
By recognizing a misconception that people have at a certain skill level you can guess their skill level quite acurately. Beginners usually want to solve the biggest of problems, and be done after the next weekend. Mid-levelers usually have specific questions about a method that must be the one true best solution in their eyes, but somehow they struggle with topic X. High skilled people usually ask questions that can't be googled, and even other experts need to look into the problem more deeply to figure it out together.
It's also hard to fake, since you need have some experience in the area to recognize how your current believe is limited. You cannot ask a ungoogleble question if you don't know already most of what can be googled about that topic.