There are some things that are beyond my understanding: The pyramids, tetraneutrons, why Heidi Montag came out with a record. I now consider Kerastase's new shampoo, Bain Divalent ($27), one of them. This shampoo is for those with a greasy scalp and dry ends — a.k.a. combination hair. Those with dry hair know what it's like to skip a few shampoos in hopes of getting silky ends, only to find your roots so greasy that by the time you do wash, you need a clarifying shampoo, putting you back at square one. How a shampoo can know where your scalp is and where your ends are is beyond me. While lathering up with it, your roots feel less oily and your ends feel silky. Of course, $27 is a lot to go (literally) down the drain, so you could also use two different shampoos, one on roots and one on ends. But if you're a busy lady with a little cash to burn, give it a try!