I've read over most of the materials on the stickies here and the borkweb site and can't really find what I want to do, which makes me believe it's not possible...

can I set up one button with a macro for elemental mastery and chain lightning so it will cast both if elemental mastery's cooldown is up, but just CL if it isn't?

I've read if the first spell is on a cooldown it will cancel the rest, but can you set the cooldown to be a condition and if it fails then cast CL?