Currently the Boostbook XSL stylesheets generate a lot of verbose output when run: to put this in perspective a complete build of the docs under boost-root/doc/ generates 3.1 Mb of messages, quite a large proportion of which are from Boostbook. Consequently at present it's impossible to figure out what represents a real issue, and what's just "chaff". So I'm proposing changing the Boostbook stylesheets as follows: * Add a new xsl:param "boostbook.verbose" which defaults to 0. * For each occurrence of xsl:message in the style sheets, we will either: * Terminate with an error if the message looks like it's a possible genuine error. * Otherwise emit a warning *only* if boostbook.verbose=1 I'm prepared to invest some time to make this work, but any comments or possible issues anyone foresees from this change? Cheers, John.