I read the link on another browser and from what I can make out is that a fatty meal enhances Cmax 6-5 fold + AUCo-^ 9-4 fold, 'significantly more' than Grapefruit Juice alone on Cmax + AUCo-^.
what I could not find in reading this research is by how much Grapefruit Juice alone increased Cmax in figurative terms [?-? fold] as opposed to the Cmax 6-5/9-4 fold fatty meal calculation.