> So you should probably limit the amount of "good code" you read when you're learning something right?

Why? If you're learning a dance, you try to copy the teacher, not other students. You don't need to study the mistakes of others, you are sure to make plenty of your own.

> don't dive into the linux kernel if you're learning C, as you'll learn optimisation strategies that probably aren't useful in your context

Unless you're learning C for the purpose of kernel programming, sure. That's not really the same question.