No because there is nothing like -WebKit-transition on it.

Then people would go back to doing their animations with JS at the cost of more CPU usage, worse frame rate and worse battery life.

Finding out whether JS is currently animating an element is about as hard as solving the halting problem.

JS timers and element modifications could be rate limited. Far far far cry from the halting problem.

I don't think so. Definitely a state transition though.

If on click it went grey then disappeared it miiight be considered animated.