The original authors have done next to nothing to improve Awk in those years; it's embarrassing to be writing another book on a subject that they have not advanced.

Awk could use improvement in numerous areas. Oh, for instance, you can pass associative arrays into functions, but not return them. Functions that filter array to array have to take an output array parameter.

Using extra parameters as the only way to get local variables is also a smell.

a[i] syntax cannot index into strings, what the hell?