Proxy auth should supersede local auth

[JB]

Hi!

Our setup utilizes custom SQL schemas and functions for authentication and authorization.
We now want to add a roaming proxy for a certain realm.
When a user logs in using this realm, our custom SQL authorization should be skipped because our functions and the roaming proxy are completely different use cases.

Our site now looks something like this:

authorize {
    preprocess
    suffix
    if (Realm == "NULL") {
         custom-sql
	 files
    }
}

At first glance, this seems to work but I wanted to know if there's a better or more common way to achieve this.
Or is this completely stupid after all? (Why?)

Thanks!
JB