The "rule" was that nationality titles were to be worn when "CANADA" or "CANADIAN" was not spelled out in the shoulder title. And, as always, some units followed the directive and others didn't. And, it was also a factor of availability. The PPCLI did not wear the Canada title during the Second WW. (The best arguments I have found is that the "C" was for Canada, and that the PPCLI had earned their fame as a Cdn unit and did not wear the nationality title to identify them as such.) Other factors came into play. Some unit names, like North Nova Scotia Highlanders were taken to be so uniquely Canadian that no nationality title was needed. However, depending on the time one checks, NNSH can be seen with the Canada's and without. There was also a logistics issue, and the Canadian army ran out of some titles and patches, especially early in the war and after the intense operations in the fall of 1944. In early 1945, new contracts for badges were held back, while Crerar considered switching the entire insignia scheme back to melton wool from printed. During this period, Canada titles were in short supply in some ordnance stores.