There's a fundamental point here. Aren't PEAR end-users all developers? We don't need those "Teach Yourself In 21 Days" 15kg books for PEAR. All that's needed is a kickstart tutorial and up to date reference. I personally don't need anything else to use a library (bar examples, which come in handy when evaluating alternatives).
Well, don't forget there are some people of just write a few scripts on the w-e or even some developers who have no time and want to use a pear package to go faster. In those case people want tutorials and quickstarts :)
I'd be very very glad if all PEAR packages had these minimum-level docs. A very big lot doesn't have a line of documentation...