You then ask: "[W]ith your super brain,maybe you could come up with a reason why so many teachers, even Univeristy teachers, seem to recall it being taught in schools in England,and overseas?"

That's easy! They've either misremembered or they were taught by idiots. Or both.

You see, every single human being "remembers" things that never happened, or at least didn't happen the way they remember it. Our memories are notoriously unreliable. We all possess false memories. Therefore one fairly likely possibility is that you never were taught such a rule but this discussion has resulted in the implantation of a false memory.

But if that's not the case, then the only remaining possibility is that you were taught by incompetents who didn't know what they were talking about.