I've noticed that a photo on one of the editions of Richard Ballantine's 'Richard's Bicycle Book' (first edition was '72) has him with a F.W.Evans without braze ons for brake cables, with sloping shoulders on the fork crown and the 'E' looking F. There's also an article dating to '74 talking about the use of such fork crowns.
http://www.bikebrothers.co.uk/evans_scans.htm