I just starting learning programming in January, and both Code and D is for digital were indispensable for the context they gave me.
However, we probably have acquaintances and relatives who could benefit.
If Kernighan explains a concept that seems obvious, it's almost certainly because most people haven't a clue about it.
I'm sort of curious to read it, too.
Now we have already C11, and AFAIK there isn't a single compiler that fully supports C99, let alone C11.
Then we have companies like Microsoft which nowadays care only about C++, and won't improve the C standard support beyond C89 on their compiler.
Plus not all projects are allowed to use gcc or clang.
Case in point, I worked in a project where the UNIX compilers used had to be the standard vendor ones for Aix, HP-UX and Solaris.
But another collaboration with Rob Pike on a book about Go is likely.