I would imagine that the author had the same feeling as a lot of us who have written and researched complex documentation that you feel like an idiot for all the missteps and detours taken to find the correct path. There is always a joy in the completion but damn you wish you had been smarter and more knowledgeable in the middle.

Certainly not to offend people. It also helps if one isn't actively looking for things to feel offended over.