Tangent here, this is my first time to ever join a forum. I hope to make some friends who are also mathematical minded. I love doing all sorts of math especially mental math. I'm a math tutor and I love teaching math to any body who is willing to learn.
Welcome to the forum!
In mathematics, you don't understand things. You just get used to them.
I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.