I too use WGO, but not necessarily for it's affects on new growth. It's my oil of choice and it just so happens to help with new growth. I've always used grease/oil on my scalp which also helps with my new growth.
I don't really "treat" all of my new growth, but I do take special care of my edges - esp my hairline and nape by making sure they always have a little something on them. For quite a few months now that something has been Sta Sof Fro Rub On....
I simply apply it to me dry edges at night on nights when I sleep with my hair in a bun. That's the only time I apply it tho....if it's not that product it's CD Hair Butter or a light oil of some kind.