For me, the story of the EF's styling is that Holden's most senior executives at the time, most of whom were American, seemed to ignore the design trends that their own corporation were moving towards. Here's the prototype of the Nova. The photo was taken in September 1960 and clearly shows Bill Mitchell's small car styling preferences at that time. That Mitchell was able to intervene so quickly, so effectively and with so little local push-back is an insight into the dynamics of GM's corporate politics of that era. I suspect that at some time in late 1961/early 1962, Harlow Gage, who was Holden's boss, had an "aha moment" and realised the the sales potential of the Falcon and Valiant, and helped open the door for Mitchell. Gage left Holden in 1962 and ulitmately became boss of the General Motors Overseas Operations in 1968 which managed all of GM outside of North America,