All the search criteria I require are
declared as properties of my node type. Indexing the content is unnecessary,
and rebuilding the indexes when they appear corrupted must take longer.
I have read the wiki page about indexing_configuration.xml,
if it is badly configured I get an error but after rebuilding the indexes
I can still find based on file content.
I added this:
thinking all the jcr:content properties
would be excluded, but that doesnt seem to have made any difference.