Currently, thorns can specify which configuration options their configuration scripts use in their configuration.ccl file. Cactus itself also reads a certain set of options. There should be a list of such options, and Cactus could warn or abort if unrecognised options are included in an optionlist. This would help to avoid user error where options are misspelled or omitted.
Maintaining such a list would also help with documentation: we could ensure that each such option was documented.