"An hour of Math is definitely going to be effective in teaching math. Why in the world have I spent my entire life perfecting my PhD level math?"
"An hour of English is definitely going to be effective in teaching how to write a novel. Why in the world have I spent my entire life perfecting my art"?
"An hour of Shop class is definitely going to be effective in teaching how to build a house. Why in the world have I spent my entire life perfecting house building"?
The point is to expose you to what is out there. Most slashdotters seem to have been lucky enough to have been exposed through other means. I learned to code because I just happened to find HyperCard and a HyperCard book at the library then learned to code TI-BASIC because I was bored in Math class and read my TI-89 manual. It was constant exposure that started
Without those two bits of happenstance I wouldn't make my living writing code as a Mechanical Engineer. The point of adding this is to expose kids to it so that if it piques their interest they can take a second hour. Or a 3rd hour. Or make a career out of it.