For those still looking for the "diagram above" in my last post, there is none. Be aware (as I still can't get my head around it) that the entries are published in reverse order of creation. So, this was definitely my bad - I should have said "below" rather than "above"....as there has only been one diagram in all the blog entries to date (I believe), other than Tim Bouma's photograph of a projection of game Bu-Short, Round 4, I think everyone will have figured it out.
I promise, as penance, I will try to imagine standing on my head from now on when providing multiple blog entries for the day! :-) or is that :-( ?