3rd, I’m going through the learning process of getting the gears right for what I want to do. So when I come to an incline, I am sometimes not in the right gear ...
I've got a friend who's been riding for years and years, and still makes this mistake. The guy has a triple, and mostly keeps it in the big chain ring, even going up hills. And he isn't even a Clyde!
So ... don't sweat it.