Right, that’s a good workaround, but I can’t do that for each line, as I need to draw many of them quickly. Think of a gradient between two complex shape objects. I have two shapes, one within another, and I need to draw a uniform gradient from the outer edges towards the edges of the inner shape. I could use a regular radial gradient tool, but it produces different results from what I want, especially if the object is long enough 
Also grass or hair, for example.
Anyway I believe it just would have been a very handy way of drawing gradient colored lines 