One or two of the excellent ones was spent, was spoiled by a little bit of er need to erm edit very carefully  introdu introduction of concepts you must be careful not to, if you've got a couple of hundred words only, but don't introduce er concepts diversity of design must of been er a phrase picked up from the video itself because it appeared in two or three of them, but it's no use talking about diversity and divine is it,de design as if , as if it's a concept which everybody else is going to understand.