this is probably the stupidest thing I have ever read. Breastfeeding does not reduce the windown for introducing new tastes. A breastfed baby has tasted the foods its mother has eaten, through her milk. A formula fed baby has tasted nothing but nasty formula until solids are introduced. Look at who funded this study. This is all to help parents from feeling guilty when they don't breastfeed. All my children have been breastfed and never had a drop of formula. No iron-deficiency over here, and they've never had commercial iron-fortified garbage baby cereal/foods either.
Feeding your baby artificial baby milk and introducing solid foods too early is not the biological norm for the human species. Whenever you deviate from the biological norm, you are taking serious risks.