Rather disappointing - Letts off form.
Similar to 50 People Who Buggered Up Britain, but without such individual targets, and less accurate. Has the author grown careless or success gone to his head? There is still plenty of clever invective, but too much that seems ordinary or nasty. There are too many metaphors and too many fail (for example good manners being like the bones of a trout, preventing it from turning into squelch, plus other rather forced comparisons.)
Much of the invective could only preach to the converted. A reference to Nevil Shute's novel about an invasion of England discusses the Englishmen's continuing to address each other by their surnames. The codes of politeness the British used (and discarded) are subtle, their purpose was subtle; you cannot just cite them and say we have declined. It's right to complain about being addressed as "mate" though. I sacked an estate agent partly for that, though like Letts, I have to grin and bear it everywhere else I turn.
This book is amusing, but it should either be thought-provoking by making you realise how and why the various awfulnesses described have happened, or else actually explain them (amusingly above all.) Thus I think Letts has deployed his furious skills too easily and carelessly.
"50 People" is far better. It is funnier, and by attaching each of its rages to Britons that embody their cause, it is more revealing and more accurate. That said, there is still a fair bit of really decent stuff in here - a paean to Hyacinth Bucket amongst plenty of others, so please don't let me put you off if you fancy these articulate rants.
Nevertheless if you haven't read "50 People" then I urge you to read that; then you'll need to thirst a bit to need to read "Bog Standard" too.