There is a subtle shift that occurs when you stop seeing your character sheet as a reflection of your character and begin to see it as the foundation of your character. When you see the character sheet as a foundation you have the unconscious assumption that whatever your character does must in some way be founded upon information on the sheet. Randomization then becomes an obstacle to achieving your vision for your character. You desire more specific and flexible tools with which to paint your character. But despite this desire for individuality, you start choosing from options
rather than inventing for yourself. Characters seem to become more alike the more possibility they get for mechanical distinction. I can point to 3e games where this has and hasn't been true, but 4e is built around allowing you to choose from options and being guaranteed safety in doing so.
I want to view the character sheet as a reflection. Then, my stats become randomly determined lines within which I may draw whatever I like. But perhaps I have it backward. Maybe if everyone were given a sheet of paper and told just to draw, most drawings would turn out to be of the same things: a tree, a bird, etc. But then again, maybe most of those people don't play a whole lot of D&D. Besides, the character sheet is not where you draw your character. You create your character at the table when you're playing. Therefore, I created this little system to handle skills not based around flexibility or specificity on the sheet, but the way I know players like to play. I've seen something like this before, but I can't remember where.