Graham,
Was this for your portfolio or for a client? If you only took one shot it reminds me of the fellow, Burke, I believe, who had 2 11x14 cameras built for him and a bunch of cassettes for the film. He drove over 1000 miles to take his pictures and exposed just 2 sheets. When he returned, he processed the first shot. It was perfect, so the other film was never processed!
How things have changed for most of us. A majority of photographers would have taken 20-100 pictures or more of the twins. Hey, they're beautiful. I'm glad to see the technical ability and judgement you have acquired allows you to repeat the essentially one shot approach as you certainly nailed it.
sure saves disk space and processing time!
Asher