No .gif this time, I didn't think to try this until afterwards. A very simple test. Each follicle may override the color specified by the hair system either completely or partially. I thought it might be a useful way of creating a white tail tip without creating a separate hair system.

Sadly, it turns out that the follicles only override the hair color parameter. You can't specify things like specular color or gradation along the hair. Those are still inherited from the hair system. So, you end up with what you see here: white tip with a light blue specular that looks good with blue fur but really ugly on white fur. Setting the specular to white or grey really made the blue fur dull and looked even worse. So, not much of a success.