This is quite a breaking change, but I think it is beneficial due to the large amount of usage of this class.
I originally intended just to remove the allocations of the two delegates handling the `Changed` flow internally, but as nothing was really using the bindables for anything more than a general "point has changed" case, this felt like a better direction.
Because the is "end glow" is when a hyper-dash is *started*, the name was confusing.
The "after-image" was already used in the code as a synonym of "end glow" inconsistently.