Oh, I totally get it now!! Sorry, "duuhhh" moment.
I realize now that you meant mixing oil straight into your shampoo and washing with that.
I actually kind of stole this idea yesterday when I was washing my hair and loved it! My scalp starts to get dry and not feel good sometimes (my sensitive scalp gets broken out when I wash with something too harsh too often), so I added some apricot kernel oil to my low poo (Organix Tea Tree Mint) and washed with that. I probably used about/more than 10 drops of the stuff by the time I was done low pooing. And it was GREAT! Thanks for the idea!! I loved it. My scalp was happy, and I don't feel at all greasy or anything like that. Awesome idea!