While we can't say for certain that there is a hard and fast rule that dictates everything, what we can say is that you should be following the deployment rules on the dataslates exactly as they are written while also taking into account any applicable FAQs.
Reason I say that is that, while the 9"+ is a common method, there are units and abilities out there that have different requirements. I may be wrong, but I think the Monolith has to be even further away, as an example.