The argument in the paper is that data professionals -- 9ncluding yourself -- do not understand data fundamentals, for which reason they blame "poor performance" on the RDM. But RDM and normalization are purely LOGICAL and as the article states, performance is determined exclusively by PHYSICAL implementation. So the article does imply that on rare occasion you may be forced to denormalize WITH EXISTING SQL IMPLEMENTATIONS, but this has nothing to do with the RDM and normalization and everything to do with SQL implementations which are not relational, do not have proper support of physical independence and are not versatile enough at the physical level.