Here's a quote from Bill Bryson's "The Mother Tongue":
Imagine being a foreigner and having to learn ... , that a sign in the store saying ALL ITEMS NOT ON SALE doesn't mean literally what it says (that every item is not on sale) but rather that only some of the items are on sale, ...
Is this true? Is it a common sign for indicating that not all items are on sale? Wouldn't it be more natural to write NOT ALL ITEMS ON SALE?
I am asking because I don't really want to blindly believe Bill Bryson, since his books, although very interesting and entertaining to read, contain a lot of factual errors (intended or not).