I would argue against your assertions. I have had good success with Noobs who don't even have a shell background picking things up from the book.

I don't suggest the Llama book to complete noobs as I have seen it confuss them. One junior admin gave up trying to learn Perl after trying to use it. He got this book and now he is on to the Llama book.

I consider the book to be a good intro and a good steping stone.