I have a primary dispatch class that implements %CSP.REST.AccessCheck() for some high level access checks before the route table forwards the request to the implementation classes which also implement %CSP.REST.AccessCheck() for some lower level access checks. The idea is that we know where we are in the implementation class and what the user is trying to do, so it makes more sense to check some lower level items there rather than trying to parse out the request at the dispatch class.