I agree with JD and Craig. One of the way flours vary from one another is in their protein ratio which will affect how much water they can absorb. More than likely, flour X is just a weaker flour requiring less water. If you don't make that adjustment the dough will behave quite differently and give a different product if you bake it the same way as the KAF dough. It doesn't mean that it's an inferior flour/dough/product, you just have to make the adjustment for it.
If you had started out working with Flour X and then had to suddenly switch to KAF, you would probably be saying that flour X makes a better product.