Don't worry, Steve - it's not all that difficult for an amateur botanist, in the UK, to grasp (it's probably an entirely different matter for an academic, professional botanist operating world-wide).

Some of the changes make a lot of sense. For example, Lesser Celandine (formerly Ranunculus ficaria) is now in a separate genus and is now called Ficaria verna. But didn't you always think that Lesser Celandine was a rather atypical buttercup? Also the Fumariaceae is now included in Papaveraceae (which it was in some older floras anyway) and the semi-parasitic genera (e.g. Rhinanthus = Yellow Rattles, Euphrasia = Eyebrights etc.) have been split off from the Scrophulariaceae and included with the full parasites in the Orobanchaceae. I could list a few more changes - but you get the general gist. All the changes are, more or less, equally logical and reasonable (a few surprises - but not many) and are included in a 'Synopsis of Families' at the front of the book.