I would extend this advice to also explicitly cover excessive use of functions: A block of code that would make sense as a standalone function/method, should n

I would extend this advice to also explicitly cover excessive use of functions: A block of code that would make sense as a standalone function/method, should not be made into a function/method if (a) it is only repeated a few times, (b) it is not complex enough for anyone to bother writing unit tests for the new function.