Concerning the Dugundji extension property

From Borgesʹ proof that stratifiable spaces have the Dugundji extension property we abstract a normality type condition and hence show that the Dugundji extension theorem is valid for an even bigger class of spaces. Borges claimed that linearly stratifiable spaces also have the Dugundji extension property. By considering cardinal generalisations of our normality condition we show that the proof of this is false.