One-Button Interrupt Macro for Druids

I've been messing around with my druid and working on Bear tanking. I like to maintain a minimalist or clean action bar, and I didn't want to hotkey multiple interrupt abilities. My solution? Macros!

After messing around, I'm pretty happy with the following interrupt macro, as it covers the various states my Druid finds himself in... either in Bear form, or in Cat form, or screwed up in shapeshifting and in no form at all! Here's the macro code:

#showtooltip
/cast [stance:3] Skull Bash 
/castsequence [stance:1,talent:5/3] reset=combat/30 Mighty Bash, Skull Bash, Faerie Fire, Skull Bash, Faerie Fire; /castsequence [stance:1,notalent:5/3] reset=combat/15 Skull Bash, Faerie Fire; /cast Cyclone

Ok, that's cool, but so what? What does this actually do? Let's step through line by line.