Brand new implementation that uses Edge Transport SOP internally.
Edge Transport SOP is faster than Find Shortest Path SOP in this case, and makes the HDA internals a lot simpler.
There are many ways to do this in Houdini but each of these methods still miss some features to have a smooth workflow, and as such they are not enough by themselves.
That's why Curve Gradient SOP still proves to be useful in the latest production workflows.
https://www.dropbox.com/s/88rc97l3pyryjg3/CurveGradient_SOP_Animatrix.otl?dl=1