I was just looking at the early photos of 'K of K' and noticed that the specimens in the 1923 Bobbink & Atkins photo and the 1917 Rose Annual photo both display a sort of raised crest or ridge running the midline of a central petal. This feature could be helpful in determining if "BL Linton Boy" is 'K of K'. Anyone who grows "BL Linton Boy" might like to keep an eye out for this feature.