I've got it setup the way you have Fleecy, with an "automatic" failover to the next clone in line when the current leader dies.

I don't have my macro to hand, but I basically used the exact format posted in the The No Focus Manifesto, and it works perfectly.

The only difference in my setup is that I have a generic "assist whoever's in charge" key instead of a macro for every spell, but that's personal preference.

In short.... what you're trying to do is definitely possible, and a very slick way of doing it, so the devil must be in the detail