@Stu – sorry, just realised I hadn’t responsed to a key point you made:
> I’d like to get to the point that you’re not a physics teacher unless you’re a community member of TalkPhysics! (Okay, perhaps that’s a bit far-fetched.)
A wonderfully ambitious aim, and one I’m pleased to support (not just because TP sits in “my domain”…). Ian’s point about building an online community certainly reflects this – that we’re all here to build an inclusive community of engaged, reflective teachers of physics, learning from each other. And this discussion is about trying to find the most useful tool for this online part of the task.