If you read Fursphere's orginal Post Balance Druid Macro /w Addon Post-3.2 in the thread it was discussed the idea of rotating the cast bar each Druid uses. On the third page Owltoid talks about about his plan to use this to manage a group of Durid's. Take a look.

And thanks Fursphere for your orginal macro, I have modified it to use the cast bar rotation method and I love it.