I love it when people proactively answer their own questions like this even when it's not the whole story -- and then fixate on the answer. When you get around to convincing them that what they're observing is not actually guaranteed, but an artifact of how the system happens to work right now, and if they want solid guarantees, please read this document over here, they have the rock-solid defense that documents are just words someone babbled one time, and they've got the code to prove how it works on their system. Theirs is the Living God!
Now, for a calling convention, this works. But approaches like this need the standard disclaimer of "please make sure you understand in what contexts the answer you have just obtained is valid". Unfortunately, most people are far too overjoyed at having an answer to consider the burdensome task of considering whether it's the right one.