When you say "smart" what do you mean?
Do you mean do you mean in the most narrow sense, as in, what is your IQ and how does it compare with the masses? Or do you mean in a much broader sense?
With the super narrow view being strictly intellectual capacity, I know I am in the top few percent, however, I am smart enough to know that IQ is pretty close to irrelevant when it comes to the real world. When it comes to seeing things from a MUCH broader prospective, I am much much lower than that. I mean, I speak only 1 language, I've only been to North American countries, and I'm not even 30 years old, so I have much less wisdom than those who've been around the world, speak many languages, and have had many more years worth of life experiences.
As far as living up to potential, probably not. I can pretty much handle any type of analytical work in the world .... but being an analytical thinker has it's downsides too.