Just tried it. It works, but the module/dist is not in the best shape:
* Test fails (pod-coverage, error in POD)
* dependency on Class::MethodMaker not yet specified
* Documentation: Synopsis contains mistake (class name is DateTime::BusinessHours not BusinessHours), the name '$testing' is not very suitable, there are typos.
* Style-wise, method naming is "joinedwords", while in DateTime families it's "separated_words" (not a big deal though).