Some programmer in AZ told me a couple days ago to in order to search their user profile database(location, department etc), instead of changing his web service

Some programmer in AZ told me a couple days ago to in order to search their user profile database(location, department etc), instead of changing his web service to accept some criteria, I should just use the GetAll() method and do it locally (a few thousand profiles), when presented with the logical use cases and the little "performance issue" he quit his job.