Q:

How can i animate an SVG stroke color transition with velocity.js? 

I would like to animate an SVG stroke color change from say, red to green. 
Is this possible? 
I have managed to do so with the "fill" property, but for some reason i cannot do it with stroke. 

A:

One solution would be something along the lines of: 
  .velocity({
    strokeRed: 0,
    strokeGreen: 255,
    strokeBlue: 0
    });

My understanding is that linear 1s should the default timing, perhaps adding a named easing will enable that, 
  .velocity({
    strokeRed: 0,
    strokeGreen: 255,
    strokeBlue: 0
    }, "easeInSine");

Also, you can simply use "stroke", but note that stroke requires a hex value, unlike those listed above which can either be unitless or a percent.