@Sadanand The article could have discussed a primer about the a priori and a posteriori paradigm. The reason academia discourages using X4 and X5 in this article is that the information from these two methods does not fit neatly in the paradigm of either a priori or a posteriori and the information used from these can be abused as a tool with confirmation bias.
Nevertheless, the article is still a useful way of showing how new knowledge uncovers itself.