Occasionally you should, but not every lap. It shows your competiton that they are a threat to you, and you should be focusing on going forward, not on whats behind.
I believe people that get into racing either have racecraft naturally. Or don't, and never will. It's a instinct. I don't think it's something you can learn. Which is why there are so many stupid moves and crashes at most races these days. Having bumpers and nerf bars has compounded the problem. I started karting in the mid sixties. Back then we had neither. So you drove carefully and cleanly. If you didn't. You paid a big price. And because of that. We had very few crashes back then.
Honestly I kind of disagree, as I feel like its not something you have naturally but a skill you build up through lots of experience (why racers that start early are typically better) but in terms of clean racing I agree with you
