When diapering baby, this mixture is very gentle, but effective. The oil leaves a light emollient on the skin to soften and protect from wetness without over drying or irritating like some wipes do. It also prevents poop from sticking to the skin and makes for an easy clean-up!
Next time you are at the store, look at the ingredients in wipes. The front of the package will say something like "hypoallergenic", "alcohol-free", and "all natural" - but look at the back. Do you know what ALL those ingredients are? If not, do you want to use it on your baby?
Another thought: too much diaper rash cream all the time can prevent the skin from "breathing". Slathering on the cream blocks the urine from touching the skin, but it also blocks oxygen, which the skin needs to generate new cell growth. Petroleum jelly is not good for the environment. And there are many studies that discourage the use of petroleum jelly and zinc on the skin for it's toxicity. As I mentioned above, coconut or olive oil is natural and soothing to the skin. If you visit http://www.earthmamaangelbaby.com/, you can get the Bottom Balm, which is a good option.