I will be reading the book in order to try to avoid out-of-context misunderstandings. Probably I'll skim over the intro chapter a bit, since I don't need a basic introduction to roleplaying concepts. But otherwise, my experience is that skipping around leads to confusion and missed context. A well laid out book presents the material in an order to facilitate understanding, and I will respect that.
(Yes, not every D&D book is 100% well laid out. The amount of jumping around you need to do to try and understand how stealth works in the 2014 PHB is criminal. But still, it's better to go in order than to skip around.)