I'm not that smart, I have just been through most of this myself, and learned the hard way. Combine that with researching answers for other people for 6 years, and being asked to speak at cancer scientific symposiums all the time, which lets me listen to really brilliant and smart people explain it all, as a by product of being there myself. Some of that has to rub off and stick even to someone who isn't the sharpest pencil in the cup. You inevitably get the same kinds of questions over and over, and therefore have what appears to be really smart answers.
I never thought I was dumb, I just thought I had really slow teachers.....