Sorry JFK. I didn't mean to imply that your technique was wrong. I have used it numerous times, often by resetting state through network via string just like you suggest.
I was just taking the opportunity to ask for another elegant solution.
I also have many other motives for asking for Generic Variables to be permitted in Formulas or to even pipe them back to inputs (although this is clunkier than need be), such as Master Tween Tracks, waveform generators, or something even as simple as tweenable inputs, or presetting state.
The dissolve rate back in to an input is limiting. Tweening it would be joyful. Generic Variable in formulas.... would be sooooo cool.