My MIL should read this article. Hell, she got some "un-petrolium" jelly to replace the Vaseline for when the kids got a diaper rash. Somehow the fact that Vaseline was made from oil made it automatically bad. We tried it humor her. It sucks, and is little better than using nothing at all. If it actually worked, and especially if worked better than the petro-derived stuff I'd use it. But regular Vaseline works well enough, and is not harmful to begin with, so screw the "un-petrolium" crap.
Oh, and FWIW, I found Desitin or A&D to be superior in any case. Desitin worked best, IIRC on the girls, and A&D worked best on the boys for some reason.