SMJ is not a procedural rule; it's a required element of a valid cause of action. It is always presumed because there's no evidence establishing SMJ absent tangible proof of a damaged individual or group of individuals.
Thanks for being honest about your conflict of interest, though.
No, it's a required element for standing. A cause of action is a theory of liability, like negligence. And SMJ is not always presumed. Take federal subject matter jurisdiction, for example. Federal courts only have jurisdicition over two types of subject matter: 1. cases that involve diverse citizens when the the amount in controversy is over $75K and 2. cases that involve federal questions (i.e. federal rights). Similar limitations also exist on the state level. Traffic courts, for example, do not have SMJ over probate matters.